When I built my roadster pickup driveshaft, I used a turbo 350 automatic tranny and rear yoke, to get the correct length of driveshaft. I slid the yoke into the tranny tailstock untill about an inch of it was still exposed, then built my driveshaft to suit. You can imagine my dismay, when a while later I was installing the driveshaft, which means that you must slide the yoke all the way into the tranny to let the rear universal move into place in the rear axle yoke---and the darned yoke wouldn't slide in that last inch!!! That one was a real head scratcher, untill Denny or Pat (I can't remember now which it was) on this forum come up with the suggestion that since it was a used front yoke, the internals splines might have gotten twisted during a "hard launch", which would prevent it from sliding in all the ways. So---I got out my trusty mag lite and looked up inside, and sure enough!!! About 1" from the bottom there was a definate "tweak" in the spline. I ran off to the auto parts store and bought a new front yoke, it slid all the way into place, and everything worked fine. I thought for about an hour that I had cut my driveshaft to the wrong length.---Brian