These two components have always been in question on the forums that cover the Bonus Built trucks. Widow maker wheel problems and the earlier Timken Detroit rear axle's lower than low ratios always have folks looking. Chuck's trucks is about the only supplier for the lower rear axle ratio for them. His are 4.11:1.
This is only one of the many swap threads:
https://www.ford-trucks.com/forums/2...xle-swaps.html
Dana 60 & 70 axles and maybe a few others had widths that can work. Driveshafts generally need mod and perches vary but some may work OK as is.