390 tranny options
You can put a semi-junk Ford 4 speed OD in there for not much. They are pictured first up here. The iron case is probably the best bet and it is still weak and you best be careful with OD. Shifter will be back in the cab methinks:
Domestic Truck Tranny Guide
Others suggest, without providing links or info like how to make the input shaft work with your pilot bushing hole, a Clark 280 out of some wrecked dump truck. Good luck, and be ready for the 36 inch shifter throws.
"Best" according to several, and NOT inexpensive: NV4500:
From the 'Articles/Specs' up top here:
https://www.ford-trucks.com/article/...nsmission.html
Another site with kit info, esp that pilot busing issue, clutch etc:
Ranger Overdrive
Note Ford uses 5 speeds in later vehicles, but those have integral bell housings. None were made for the FE bell pattern.








