To install an R10 Overdrive in a light truck, you must have the complete unit with its three speed gearbox ( 52 to56). A 3/4 inch adapter plate must be made for the front of the trans and the column shift linkage must be significantly reworked. Also the driveshaft must be shortened.
However US built trucks may differ from my Canadian model. Their transmissions were not all the same. In any case, I have found my installation to be very satisfactory. The most challenging aspect was to make the parking brake work.
The R10 J as found in 57 to 59 cars has a rather long input shaft which makes it unsuitable for some applications. Dodge B4YA gives the best advice, above.
Elsewhere on this forum is a thread discussing truck transmission choices.