Definatly headers, with the vortecs you'll need a new intake designed for the 18degree head. HEI ignition if you dont already have that. How's the carburetor condition? Cooling fan? Suggest running electric fans or at minimal a fan clutch instead of direct drive. How's the cam? A cam matched with vortecs power curve will make alot of difference also. 2 1/4 exhaust system.
GEARS. 3:73's with a posi will make a large improvement.
Maybe even a small shot of the squeaze
I dont think you would get into much trouble with a small 100 shot of nitrous (might even jet it down to 75). With that, you should have no trouble "shinning the light" (tail light that is...) on your friend.