What options for O/D behind a S/6?

At this point, a non S/6 swap is NOT an option. FWIW, I average 20-22 mpg in my 4400 lb '93 Dakota with 3.9l / AX15 5spd / 3.21 8-1/4" and cruise control. And it weighs a WHOLE lot more than the Valiant. Currently only looking at S/6 O/D options, I have a strong 40k miles 225, with A/C components already installed. Also a40ish k miles 3.9l saved from a destroyed van body due to how well it ran, again with a/c components installed. Either engine coupled with a '62 dealer installed underdash A/C unit fixes any FL specific short coming we may have to overcome with this car.

Mike in FL