What to do with my suspension on 71 GMC

[Hibred]

Hi, guys bought a 71 GMC last summer, its a pretty truck, all done in a Harley theme, orange and black, originally from Arizona, has a 402, 400 turbo and near mint interior and has been lowered, now here is the part I could use some advice on. The lowering is a bit much if your not careful the headers can and will hit so would like to raise the front up a couple inches and now the rear is where I see the most problem to me, it has a leaf suspension that is under the axle, rides hard, what can be done with the rear. If I am going to raise the front with some different coils can the leafs be changed over to coils with a kit, which kit is best and how much would I be looking at, is it something I can do myself, I have a hoist. Throw some ideas and suggestions out there, thanks. Oh, one other thing, I would like to keep it reasonable as possible too.