C10 and C20.. whats the difference!?!

[young.gun]

So guy's i just picked up my 2nd 67-72 a week ago it is a 1970 C20 leaf springs in the back 396 big block is going into it and th400 it is completely rust free with 1 dent the size of my fingernail and i bought it thinking i was going to lower it and make it a 70's style hot rod. (im a 4WD guy this is my first ever 2WD) i soon found out that one dose not simply lower a C20 a little bit its either 5" or nothin basically, so now im steering towards the idea of a 2" drop in the front on 28in radial T/A's but my big question here is what was different about the C10 and the C20?! theres so many C10 parts but next to no C20 parts? what aftermarket suspension C10 parts fit on a C20? who makes the best parts? hows the hotchkis stuff? this truck will be a daily but a drag truck too so guys whats your answers??