6.5 td swap to 5.3 ?s

[mcnally351]

So I have an 01 gmc c3500hd cab and chassis work truck sporting an anchor 6.5 that is giving me trouble . Doesn't start if it isn't 80* out and now is smoking horrible with some valve train noise. Truth is it could probably be fixed but I have no desire to work on this turd. I've replaced cracked heads on a 6.2 with all the hard lines, it's sucks.

Anyway, I love the truck it has a huge frame and I have towed over 5 tons with my dump trailer. I'm thinking of doing either an ls swap or a cummins.

My question is will a ls bolt right up to my 4l80e? Do I need to change the bell housing? I'm aware of most of the conversion parts because I'm swapping my k5 blazer over , but I had my harness modded on the blazer but I've heard guys doing a four wire hook up to the obs Chevys? I know my truck has a drive by wire now and electronic trans can it all be controlled by the ls harness.

Sorry lots of questions but trying to plan this repower. I do have a 6bt also that I can swap over but it's in a working truck. Thanks-