Black Anodizing

Does anyone have any experience with black anodizing and
engraving aluminum?

Here's the dilemma. I need to engrave a couple of sheets of
aluminum, have them black anodized, then paint the letters
with white paint. I tried this once and everything was ok until
I tried to get the paint into the letters. I figured slop it on and
wipe the excess off with acetone. Well it smears the paint into
the black satin finish and no amount of cleaning will get it off.
It doesn't look too bad but it's sort of a dark gray anodized
finish now. No matter how careful I was I still got paint on
the surface when trying to get it into the letters.

The guy at the metal finishing place told me most engravers
paint the letters, sand the aluminum, then black anodize it.
The black dye does not stick to the paint and you are done.
Problem is he didn't know what kind of paint to use. Also,
don't they etch the surface first, and if so, what will that do
to the paint. I was thinking of using epoxy paint.

Any ideas?

Thanks
Bill