97 Dakota tranny problems "Code P0740"

[CoraZuki]

Well, I guess my Sammy is now "officially" my DD.

I have a 97 Dakota with the 318 and Auto tranny that I flat-tow my Sammy with.

It just started shifting funny in 1st and 2nd and the engine light came on. It gave me the Code "P0740 TCC Circuit Malfunction". I took it to a shop to have it checked out with a scanner while it was driven. The mechanic told me that all the solenoids and sensors were working fine, and that the problem was in the tranny or torque converter. He advised me that the tranny could overheat on me if I drove it on the highway a long distance or if I towed anything with it.

So here are the questions...

1. Are there good remanufactuerd trannys that would hold up better for towing than a stock replacement?

2. Is there a manual tranny that I could swap into the Dakota? I can weld and modify things so adding a clutch peddle is not a problem.

3. Are there other engine/tranny combos that I could pull out of a donor vehicle, like a 5.9/manual, 5.9/auto, or Cummins/auto?  Within reason.