Hey fellow GM people - got my hands on a 97 c-1500 (maroon SWB reg cab Cheyenne 4.3 , 5-speed! me and Dads since new)

Me and dad bought this truck together, now he's finally handing it down instead of selling it.(When I got married 2 years after financing it I handed it back to dad in 99) It is in great shape , except high miles, in its life its had trans bearing repair, alterntor, starter, battery and oil/ fluid changes - still sits on original shocks - 265900, original a/c works good... its also had a fuel and water pump radiator, oh and brakes.......many miles whrich many of them are highway. He drove back in forth from lake charles to baton rouge for years .... A couple of questions, what wheels and tires look good on these trucks and I am interested in making it faster - I am interested in a (4.3-v6) to (5.7 -350) or (325 5.3) or possibly 454ss project.gas hog though..its a work driver and play toy - would be a cool red light to red light "sleeper" too... So how bout some thought and some pics would be cool... I was wondering if 15x10's look too wide, or is a15x8 just right - Light me up with some feedback ol mighty chevy dudes.... THANKS AND TAKE IT EASY....p.s. I like the American Racing 61 series on 15x8's 255/70's what yall think??