A body 904 tranny fit in a 1983 dodge prospector truck?

Yes.....but.....you will need a 904 converter and longer driveshaft. Don't forget that 318 balancers were neutral and 360 were counterweighted. and some had lock-up converters. They don't interchange. Some trucks did use a 2 piece driveshaft but I don't know in what years and/or applications. Some truck transmissions also had a short tailshaft! I don't know if any linkages would be different.