im in the process of prepping my new cowl hood from goodmark.
has anyboby done this before if so how is the best way to prep it before painting it ? such as what grit of sandpaper and things like this. and what not to do etc. etc. thanks, DAN

Here's what I did on my goodmark hood. Scuff up the whole thing with some sandpaper. I did 320, or was it 220, on the top and shot it with some primer surfacer. On the underside I didnt apply primer and sanded with a combination of 400 and 600. Block out the top being sure to get rid of any imperfections. Oh, before you do anything you should thoroughly drench it with grease/wax remover.

I work at a body shop and here is what we do with any part that comes in, and the hood isn't any different. DA sand the entire hood (outside) with 320 grit. Then scuff the underside with a scotch brite pad. We use the brown ones. Then seal the underside and paint it. Then use the sealer on the top side and paint it and your done.

We do the same at our shop as what 72chevylwb said. Get the shine off the underside with the scotchbrite pad and paint it. Make sure there is no texture left on the top side. Breaking through to bare metal on the top in a few places is not a concern.(edges and bodylines) Use a sealer on both.

A side note: Sikkens recommends that the underside not be sanded at all. Their sealer will bite into the factory primer without sanding. I worked at a Sikkens shop for a year and there wasn't an inner panel that was scuffed before painting. They never had a come back. Still, I would scuff it, just for peace of mind.