I own several of the one ton trucks and have swapped center sections etc. The Rear ends all appear to be same width with 5:17 to one rear ratio. Cab and chassis had dual wheels on rear and different front hub that carried the dual wheel up front. 9 Foot Pick Up bed trucks had single wheels front and rear.
I have 1949 one ton with Cummins Turbo Diesel and swapped the rear end out of the 90 Dodge truck into the original Chevrolet chassis. It now has 3:07 to 1 rear ratio. This rear is from a 90 Dodge dually and is wider than the cab and chassis trucks, but I run dual wheels front and rear after swapping the front hubs. This leaves a longer portion of the axle sticking out but as long as you don't try to bend it with your shins its fine just ugly!
