It's always been a mystery to me why Chrysler didn't put 4 speeds in the Lil Reds to begin with. My first Dodge was a '77 D100 Slant 6 with the tree onna tree. The trans was worn out, and I picked up a parts truck with a good stepside bed and the 4 speed overdrive. Swapped it out. That truck was a blast to drive and got great mileage. I'd live to put a 4 speed behind the 360 in my '81.