Now... (As Paul Harvey used to say...) the rest of the story.
I took my transaxle down to Kevin at Catellus Engineering, and even though it was prime rebuild season, he fit me in soon after Christmas. He sent me a bunch of in-process pictures showing me what he found and it was all done by the end of February for what I would consider a very reasonable price for a Porsche specialist.
Kevin gently shared that the problem I had was because I had inadvertantly put one of the shims from the mainshaft onto the pinion shaft. (whomp-whomp
) But while he was in there, he went through the box to make sure that everything else was set-up correctly, and also replaced some pieces (like the rocker-arm for the throttle) which I hadn't replaced, but should have. He even got the shifter seal installed so that the transaxle is no longer leaking very aromatic gear lube all of the exhausts. Something that I was never able to do. My wife is so happy that the garage no longer has that "stinky 911 smell".
I finished putting the drivetrain back into the car (again) last weekend, and I got the car successfully through inspection on Saturday. Kevin was even nice enough to take a ride with me this evening to sooth my "what is that sound?" jitters. I've never driven a 911 with a virtually new 901 transaxle. Everything seems great and I have to get used to the new synchros breaking in for a few miles. So I guess I just need to get back in the car and keep driving it.