I picked up the adapter plate and shaft coupler from Brian Berrett (Wilderness EV) at the same time that we picked up the batteries. I also bought (traded batteries for) a flywheel and pressure plate from Brian as well.
Spencer and I spent some time loosely assembling everything to see how things would go. Spencer was very impressed with the shaft coupler, some high quality machine work there.
Motor Shaft goes in the coupler here:
Flywheel goes here, with 4 bolts. This is the back side of the view above. Yeah, I need to get some better pictures of this...
Coupler mounted to flywheel:
We then got the motor out and test fit the adapter plate. This is when we noticed the first problem: the mounting holes didn't match up. Too small and set at too small a radius from the shaft. Turns out the hole pattern matches the back side of the motor. Easy mistake to make, since the plate was made from a drawing that I had sent to Brian.
There is some good news on this front though: on Monday Spencer confirmed that the center hole fit nicely around the collar of the motor. This is most important hole, since it ensures that the motor, transmission, and clutch all stay centered. If they aren't centered, there will be some wobbling...not a good thing. Spencer also drilled some new mounting holes, correct size and placement. There will be a bit a few extra holes but it should be fine.
On to problem 2: We also test fit the adapter plate on the transmission last week, and the holes didn't seem to line up right. Spencer doesn't have the right size bolts, and so we won't really know for sure until we try it. It seems very unlikely that the transmission side holes on the plate would be off, since Wilderness EV specializes in adapter plates for VW Beetle transmissions. Talking to Brian on the phone, it sounds like there is often a bit a play in these holes, and that the hole near where the starter motor used to go can sometimes vary by 1/8th of an inch.
Adapter plate, test fit to trans. The 4 holes on the near side are too small and too close together:
Motor front side. Notice the larger holes, larger spacing:
Compare the above to the back side:
Check out a bunch of pictures of the motor, clutch, adapter plate, and coupler.