Self,
Welcome to Stovebolt.com
1947-1955 (through mid 1955 Z-series) GMCs were named New Design (ND) Trucks, and 1947-1955st (first series) Chevrolet trucks were named Advance-Design (A-D) Trucks.
In many regards, the GMCs & Chevrolets were very similar, having different front-end sheet metal, and different radiators, engines, and front frame design and minor dash/gauge differences (47-53). GMCs had positive ground electrical systems and Chevrolets had negative ground electrical systems.
Nevertheless, you will find a lot of help here. In each new thread/post/question state the make, year, model of your truck.
There is another discussion board that you might find helpful:
oldGMCtrucks.comHowever, there are probably many more members here who have done conversions similar to what you are thinking about doing.