You won't need to do a lot to the trannies to get them to hold the torque you are planning to throw at them.

I would suggest that you take the OD units to a shop familiar with them. Their experience alone would be worth the price of admission.

A&A Transmissions is the go-to source for parts and info. PATC is another good one.

Good parts, good advice, good line pressure, a good valve body kit and you're good to go.

Lenny at Ultimate Converter fixed my PTC problems, so I would recommend a conference with him on the converter..