jeff-
the gentleman you mentioned was probably using a f**d t5, as they have a different bolt pattern than the chevy t5. the chevy variant has the same offset 4-bolt pattern that's on the older chevs. the one i pulled from an '85 camaro bolts up to my '57 bellhousing. the bolt holes on the t5 need to be drilled out slightly as they are sized for metric bolts, but after that everything fits great.
for your '37, you want to look for a t5 from a chevy s-10 pickup, as it will have the optimal shifter location... or, if you want the best setup, take the main body from a camaro t5 and combine it with the tailshaft from the s-10 t5. that's what i'm doing for my '31. t5's are extremely modular transmissions, so you can swap parts around like crazy. i'm not sure about the 250, but with a 235 you need to trim 1/4" from the face of the t5's input shaft to make things work.
if you're interested in this swap, i suggest you check out inliners.org's tech section for a good write-up on the swap. i can also mail you a photocopy of the instructions and drawings that brian logan from the hokey [censored] message board sent me. his instructions are very thorough. also, you can ask me questions... i may not be your best source though, as i'm only about halfway through the swap, but i'm learning a lot.
for more information on the t5, check out:
www.5speeds.com/t5/index.html ps. while the camaro t5's can be hard to find and expensive, the s-10 t5's are all over the place. the local u-pull it yard has two for $70 each.
pps. you'll have to go to an open rear.
