Welcome!
Thorough inspection; suspension, brakes, oil leaks, tires, belts, hoses, fan clutch.
replace belts, hoses, air filter, etc. as needed. it's worth emphasizing. brakes are important.
Replace the fuel filter, chances are you have no idea how long its been on there.
Thermostat ...just replace it. so many times, ive tracked a problem caused from PO installing wrong t-stat, defective t-stat ...no t-stat. just replace it. At this point inspect and test the coolant, if it's questionable, change it.
Check EVERY fluid, all of it. most people never change trans fluid/oil, diff oil, t-case oil.
cleaning and retightening grounds (every ground on the rig) is free and will often cure a lot of "gremlins"
these rigs are greasable, climb under it with a grease gun and lube everything.
otherwise, give it good cleaning and go enjoy it.
if you decide to mod it, just be honest with yourself about what you are trying to do. sometimes a small body lift and tires is all that's needed to get "the look".
...sometimes you need lockers and a sawzall ;-)