If the truck drives nice as it was stock,why not chase the free horse power?
first,there is no such thing as "free" horse power,lol.
What I think would make you happy is to completely rebuild and blue pring your engine with stock or stock replacement parts,,,but,,,go the extra mile with a perfect job of assembly.
when the block is bored 030,also get the block align honed,squared and decked as close to perfect as possible.Buy an after market,"blue print" replacement cam. This is a "race cam" but it is based on original equipment specifications. So it will idle the same,sound the same but have a little better breathing due to slightly more aggressive ramps and a lot less variation in cam lobes(just more accurate grind with precision in mind) balance the engine,custom hand fit each piston and ring set,resurface and quality valve grind.
This will net you all of the factory rated power and a little more. should last 300k plus.
when its running a custom tune will be in order
Fbird will explain spark advance and fine tuning of the carb(hope its a quadra jet)