I might be wrong, but I think aluminum 833s are OD?
If you can get them cheap, buy em. Just make sure you have an A body tail housing (shifter location is specific to A bodies) and then you need a bearing retainer which matched your bellhousing which matches your flywheel. If you checkout brewer's website you'll find a ton of part numbers and years and info by looking at the parts in their catalog.
The pedal assembly is probably as important as the trans too.
The bell housing can be tricky because lots will fit, but the clutch arm and pivot are often slightly different which can cause linkage headaches.
You'll get it figured out though. It's really simple, but sounds complicated - it's not.
I would want to assemble the car at least mechanically before sending it off to a body shop too. Nothing worse than having to grind or beat on new paint and slipping..
