Guys,

I just spoke with Denny at Denny's Driveshafts, and I have to say that he was a TON of help. We're both betting that my TH400 is a threaded "truck" or "bolt-on yoke" style, which I will verify tonight. If that's the case, there is indeed a counterbore inside and a counterbored slip yoke is made to address the issue. All I need to do is verify my u-joint cap measurements tonight along with the driveshaft and order the correct yoke.

Thanks everyone - I guess the learning never stops...

Hobo