I just recently bought a 1986 Aria pro II zz custom. It is a beautiful guitar that i plan on restoring.
The guy i bought it from said that it has a cheap black finish painted over the original factory pink/purple burst.
I would like to do a holoflash finish on the front, with a gloss black finish on the back and sides.
I would probably sand off the crappy black finish, and scuff up the factory finish and paint over that in a black finish.

HOWEVER, i dont know what type of paint to use as the basecoat before i iron on the holoflash film.

And i am not using the stick on holoflash, im doing the real holoflash iron on film
If the film is opaque then surely it won't matter what the finish is, so long as it's smooth? Project guitar has an article on this (http://www.projectguitar.com/articles.html/_/tutorials/finishing-refinishing/how-to-do-a-holoflash-finish-r114), I'd go with scuff sand the top smooth and then go wild with the film.
My Rig:
American Standard Telecaster
Fender Starcaster
Sp. Edition Jack Daniels Strat (Modded)
Vox AC15CC1

Stuff I've Built:
Telecaster Deluxe
Telecaster Junior
Pedalboard (from a shelf )
the odd pedal