[yfs200p]

Ok, so my buddy totalled his 86 K20 the other day, and he told me I could have the axles, rims, and tires off it for $200!! so i definitely think i'm going to go for it. But what i need to know, is how hard is it to convert a k10 to 3/4 ton? Would i have to get a new rear driveshaft? or is my 1/2 ton one OK?
And also... how bad would 4.10 gears be with 33" tires... i have 3.08's now and love being able to cruise 75-80 no problem. Will my truck even get going that fast with 4.10's? oh man this is a lot to think about, well i will snatch up those axles anyway, and if i dont use them, i'll throw them on the board for sale, so keep your eyes peeled... give me some advice, THANKS