Mike, I had the same idea, removing the frame and powder coating. However, getting any of the screws to budge was near impossible. I chalked it up to dissimilar metal corrosion. Plus, I couldn't figure how I was going to transport the frame seeing as it wouldn't fit in my small SUV. Maybe if I had a pickup truck...
Anyway, I decided to do it the hard way, which was to scrape off the old paint and re-paint. Yes, I know painting aluminum is hard, but I figured it couldn't look any worse and maybe I'd have to repaint in a few years.
So I went at it with a combination of scrapers, putty knives, sandpaper, sanding sponges, steel wool, Dremel, etc. and got 95% of the paint off. Once that was accomplished, in looking at the result I decided to leave it as bare aluminum. It pretty much matches the door, which, in my case, is also bare aluminum.
It's been that way about two years and nobody has ever made a negative comment about it so, for now, I'm leaving it.
If you have the painted door, a bare frame might not look good but if you have the aluminum door you could consider this approach.