Any LowBuck but STRONG overdrive option?

67Dart273 said
No Mopar auto is an easy swap. You would want an earlier "H" (hydraulic) IE 46RH as opposed to an RE (electronic) out of the later vehicles. Hydraulic ones are hard to find. 727 based are not an easy physical swap and either 904 or 727 bases swap requires extensive crossmember re-fabrication There are threads on here showing some good details.

There is what is called gearvendors but they might be "cheap"

A friend of mine dad builds a 727 he was a tranny guy so masshole through the car in reverse and screwed it up but that's a 3-speed he said he had a lockup 727 he gave it to me actually it's sitting over in the yard but I don't know if that's actually a 3-speed lockup or not