A 5.3 vortec is an LS motor just an fyi. If you plan on using the power of the 5.3 you will thank yourself for beefing up the trans now and you should at a minimum look into a Ford 8.8 rear axle and I wouldn't plan on going with much more than a 31 inch 32" tire unless you are doing a straight axle swap or really just want a mall crawler cause you will snap your front axle shafts like toothpicks with that power and bigger tires. I went through all of this a years back and started with the straight axle conversion and bought most everything needed to do the 5.3 swap and then ended up trading my blazer before I got to do the motor swap so now I have a motor and lots of parts to do the swap but nothing to put it in sadly.

Well she's gonna be a pavement princess, since I'm looking to get a K5 for my trail riding, much rather have a beater than a truck that was taken care of most of its life. Power wouldn't be used "much", more for show than anything and plus just seems like it is more logical considering the 4.3 uses the gas of a V8 and has the power of a 4 cylinder. A 5.3 would be better in my opinion.

I've toyed with doing a SAS, but haven't decided fully yet. Do I want one? Hell yeah. Am I great at fab work? Not really. Am I a good welder? Nope. Also there's so much flip flop about what axle to get that will let you keep the trans stock and shift properly and such. I haven't quite decided yet but it's there.

I think I'd end up sticking with a 6" lift and 33's, if need be get a 3" body lift and stick them on then. The power wouldn't be used until it was snowing or if I needed to get in the yard for something.