I am getting ready to clean up/paint the A/C box what is the best way to clean that up and prep it for paint and what is the best paint to use? Thanks in advance for the help.

to my knowledge, they are not painted, you can usually see the fiberglas. Possibly clear coat it.

I used 0000 steel wool and lacquer thinner, cleaned the outside box like new.

I cleaned up mine with Laquer thinner and then fogged a mist coat of SemiGloss black over it to bring back the black color. Really not much paint at all, just enough to add a hint of color to it.

Thanks guys,:thumbsup It seems that laquer thinner will do the trick.Ill try the steel wool first and if I need to then Ill add the color to it. :