Has anyone tried knocking the silver powder coating off of 90's era Shimano parts and polishing the aluminum underneath?

I am looking at a set of 1990 105 cranks with intent. I have a spray can of airframe stripper, sandpaper, and a buffing wheel.

The alternative is dumpstering the poxy looking things.

Yes, They come out looking like this:

I hand polished a '90 painted 105 crankset, first with #100 sandpaper as it had some deep scratches, then with 220/400/600, coarse and fine auto polish. It took about 3-4 hrs work to get a mirror finish.

Easily done, but not quickly. Looks great. The aluminum will develop a slight hazy look, not quite mirror-like, over time. Because it's aluminum, that's all.

It's probably clear anodizing, in which case the stripper will do nothing. The best way to test it is to put the stripper on the part and see what happens. If nothing happens, get some Easy Off.

Tripoli compound works best for polishing aluminum. I use 0000 steel woll between the sandpaper and the buffing wheel.

Be careful with paint stripper, I once did that and aluminum turned matte gray, and I mean dark gray.
It is best to use something like 400 grit wet-sand sandpaper, than 600, and than for even finish I use Cameo copper cleaner, or Comet scrubbing powder on a wet rug. And just buff it as best I can. After that I use chrome polish either on a towel and buff the part for a couple of minutes, or use a buffing wheel with chrome polish in the drill. That brings out the mirror finish. You can get most polishing pasted at any auto stores. After a while it gets addictive, whenever I see unpolished aluminum, I have to make it shiny.
And don't forget to wear a dust mask!

bingo.

oven cleaner in a bucket to strip the anodization, then sand down. I usually do 200/400/600/800/1200/1500 and if I've got some time to kill, I'll keep going to 2400 or 3200. Then finish it with some polish. With most aluminum, it will oxidize (as mentioned above) unless you seal it with something like zoopseal... if unsealed, you'll have to polish it every now and then to keep it looking good.

I have six bikes with stripped and polished parts. It's not that big a deal to keep them polished as long as you don't touch the parts with your bare hands.

OFG, That's what I was hoping to find under all the bad paint and crud. Did you de-anodize and polish the chainrings too? Looks great.

I started today, and Dirtdrop, it is paint, not anodized, I could tell because it looks like paint.

Got the left arm sanded and polished and the right arm sanded so far today.

It works, but it's a lot of work *sigh*.

I can't remember where those rings came from, but I didn't do anything to them.

The bike was a flipper from a couple years ago.