Citro6.0

Im reaching out for an answer on the compatibility of a 2002 gmc 1500hd rear end and a 2500hd rear end. I’ve been looking at aftermarket rear differential covers PPE specifically and on the website all I have found are ones for a regular 1500 which appear to small and a 2500hd which appears to be the same 14 bolt which is on my truck but with a full plug that my diff cover doesn’t have but I’m not sure if they are different rear ends or if the only difference is a full floating rear end versus a semi floating rear end I’ve found no answers on other forums so I’m making my own post trying to get answers