changing front

[Porkchop]

I have a 69 3/4 ton and I want to lower it to look like a fast street muscle truck, but I don't want to slam it. I would also like to switch from the 8 lugs to the 5 or six lugs and I figure I may as well go for the disc . So, am I looking at changing both the upper and lower control arms along with the spring and the spindal assembly. I wish I could give you guys a specific drop height but I don't know how to identify what I want. I was hoping to be able to pull the parts off of a half ton truck and get the height I want. I hear the that mid to later 70's chevy trucks have discs and are a straight swap, right?
thanks for helping out someone who doesn't know a lot.
brad