Boy, for someone who wants to keep it stock you have a list of possible mods.
IF you want to keep it stock, do the 3.55 R&P, 16-inch wheels with 30-inch diameter LT tires, 12v conversion and swap out the engine for a 235 6-cyl. I did front disks on mine but if I had it to do over I would have restored the original Bendix system.
Those simple modifications will leave you with a very stock looking truck that will make a strong and reliable driver.
IF you don't want to keep it stock, drop in a SBC, 5-speed overdrive transmission, Camaro rear axel, aluminum wheels, disk brakes and an IFS conversion.
Keep it stock, the world is saturated with hot rods.