85GT my 4th foxbody

flush/replace all fluids-oil,brake, trans, rear, ps, gas,coolant, and all filters-oil, gas, trans, air
replace plugs, rotor,cap, wires, wheel cylinders, brake hoses, radiator hoses, thermostat. belts
remove all spark plugs and squirt a little oil in each cylinder- turn the motor over by hand to make sure no rings are binding and the motor turns over
I would remove the coil and crank the engine over to make sure you have fuel pressure and no gas leaks.
lubricate the throttle cable and TB springs
I would pour about 8 ounces or so of MMO in each side of the top end to free up any sticky lifters, valves, rings.
check the TPS voltage
Don't be surprised if you have gasket such as rear main seal, valve cover, pan ,etc. that leak from dry rot. and that your injectors may be stuck or in need of cleaning.