The Creation Of A Spit6

I decided to do this under the car, as most will be in that situation. Mine was almost empty, as it's a new install and was drained before I put it in the frame.
Couple of things I considered before I started, go with a small plug in case things don't go as planned, be very patient.
You will need a 1/8 inch NPT 27 plug and tap, in most small tap and die sets. Oily rag, you will wipe the drill a bunch and this will help collect the fibers, see picture.
A 21/64 drill, better a "Q" tap drill, couldn't find one right off hand and didn't want to wait. I started with a 1/4 inch drill first.and after the 21/64 I touched the outside with a 3/8 one, just to aid in starting the tap. Be aware of the amount of depth you will be able to get the tap to go, once it hits the crown wheel and you try to go further, you will rip the threads out, not a bigger hole is required..
Drilling case iron is not much different than regular metal, just not getting long slivers of metal. The depth of the hole will surprise you and is good to know, right at 3/8 inch and you will hit the crown wheel a short distance from clearing the hole.
A oil pan should be in place, as I got a good bit of oil coming out and it had drained for a couple of days coming out of the fill hole in the oil pan. I flushed after drilling and tapping with 30 weight oil.
Getting the tap started.correctly is a big deal, so take your time. Turn the tap only a quarter turn at a time and then back off, you will be able to feel the cutting and the threads get clogged up, so after one full turn or so, take it out and wire brush the tap to clean it completely.
I used a brass plug that was 1/2 inch long on the threads..
The plug ended up with a nice snug fit with a couple of threads left or exposed. Should work a treat, if not, I can always add some thread sealer. Lets hope not.

Had A Do Over
Just to add and let you know that the 1/8 NPT is a bit small and I could see it being a problem in draining. So went with a 1/4 NPT 18, the only difference was a 7/16 inch drill, slowly is the word here, the tap is kind of a one or one and a half turn at a time, take it out, clean threads with a brush and oil, install and turn some more. I used a half inch ratchet with a half inch socket on the tap. Hand started, don't force it, a broken tap in that hole will be a major problem.
Wayne

I have most of the dash ready to install, that will be the easy part. Getting all the wiring where it needs to be will be fun.
The only change will be the choke handle, it will be the "T" ones like the old GT6 had, goes with the older switches.

OK, you guys have officially shamed me into doing my dash.
This is the start, as it's a '78 Spit6, it will have all the original toggle switches of the early GT6, even the rocker hazard one. Double gauge (temp/oil) in the center and fuel on the left and amps on the right.
All the work was mostly in the rear, as the toggles have short shanks for install.
Of course the charger will be on the right bottom and choke right top.
I kind of hate to cut it in three sections but for ease of install a must.
Still need to experiment with some stains, but it looks pretty good like it is.
Now if I don't screw it up routing the holes for the gauges to be recessed.
I guess the Jaguar XK8 had more influence on me than I thought, as it's very close to the grain and color of mine. With black gauges should look the way I envisioned.
We had a very warm day, so I was able to get another coat on. I'll get some pictures later or tomorrow, closed up the shop after getting the shifter for the GT6 transmission rebuilt. Oh, I did snick out an get in nine holes, shot 35, so the fumes must agree with me. LOL
I used Fostner bits for the back side, was able to adjust the drill to only go so far. took two different bits for the switches, that little 1/16 inch shelf was a 1 1/8 and the outside 1 3/4. Like you I just got a trim router for the countersink and the heater control housing area. Used the old dash for the big holes..
I find it very UN-nerving the further along you get. drilling holes in the plywood, OK, now putting the veneer on and cutting the holes out, a few palpitations, routing the countersink, can I go slow enough, it grabs a edge and splits the veneer where there wasn't enough glue, call 911. You get the picture.
Lucky I found out how to do jig saw puzzles and put it all back together.

The lay gear will come out now, the large thrust washer goes in the front and the small in the back, the slot will let you know which is which. The needle rollers are held in place by a small ring on each end. Do not hurt these, they are expensive to replace, I just take the needles out and leave the ring in place.
The reverse gear shaft is held in place by a one bolt on the bottom of the case, It just pulls out, take note, it will need to be lined up with the hole when going back in.
Now, the case should be empty except for the reverse gear slide.
Time to clean all and order parts.

Moving to the front, the first synchronizer should have already fell out of the front off the hub. The hub is lose, as the only thing holding it on is the input shaft. Holding it in place is a pain while pressing out the rear beraing is one pain in the butt. Don't clamp a pair of needle nose vise grips on there, the roller bearings need a smooth surface. Speaking of roller bearings, by this time they will be falling out of the layshaft all over the work bench, just as information, be sure to collect them all, you might be reusing them, hope not. There are 25 on each side of the shaft.
Next the fun of taking out the circlip holding the gears on the shaft. I used a small thin screwdriver to pry it out then a pointed small awl to pry it up. Takes a few tries. Then there is washer, gear, thick thrust washer, gear, thrust washer (small), synchro and hub. Both the synchro hubs have synchronizer on both sides, they fit in slots, so kind of hard to get them in the wrong way.

Will do this in several post.
Did a tear down of the GT6 transmission today.
Getting to the main shaft is pretty straight wrenching. The rear bearing wants to be a little difficult. Took some photos of the gear orientation. plus the speed odometer gear can be tight, but most repair manuals give a procedure for removal. Lucky me, I have a press. It can be punched out with a brass punch, but not the best idea. Be sure and take the lay shaft gear shaft out before starting any top gear procedures. If you have a dummy shaft (1/2 inch wooden dowel) cut a 1/4 inch less than the inter measurement of the length of the inside of casing.
The front bearing will generally come out with a few taps of a punch after the front case is off. Replacing the bearing requires getting the spring clip off and pressing the bearing down the shaft.
Reverse gear needs to be paid attention to, it can get locked up in the rear gear when pressing the shaft out of the bearing. Just keep looking at it and if you feel a stop, don't do any more pressing or pulling until you know the gears are not binding. The rear bearing must come out the back of the main shaft to get the gears and shaft out of the casing. They lift up and out the top of the case. The rear bearing will have a washer right under the "C" clip.
From the rear, Thrust washing with smooth side toward bearing, gear and spit washer that is properly laying under the lay shaft, because it fell out when the gears were sliding around. There is a syncro in the back and front of the hub. As much as it looks like it the next gear doesn't come off the back.