OK, here's how it went:
Started off with a stock Matte Black/Grey Fatcat and an already somewhat customized Whiskey/Bronze Fatcat with the brown fade coating already scratched off (thanks again to zev5740 for doing the hard work).
The Black pair suffered from the early production "lens rattle" that was experienced by some on the forum. I got them on eBay, and since they were an extra pair for this project, I didn't really care too much. I found out at HQ that the lens rattle is a lens problem (lenses cut too small), not a frame problem. Since I got this pair on eBay, they wanted to charge me $29 to replace the lenses. Nope. I had another idea... but more on that later.
Anyway, I popped out all the lenses and carefully pried off the icons using a pin per Lee's expert tutoring. Here's a picture of the clear frame with nothing on it:
I ran into a little snag with the gunmetal icon on one side of the Matte Black frame. The metal icon is just a "shell" over a plastic substrate with foam adhesive, not a solid metal piece. While trying to remove it, the shell popped off, leaving behind the brittle green plastic and adhesive still stuck to the frame. I managed to get it all off and put back together with the shell. After I stuck the icon to the Clear frame, I noticed that it was pulling up at the edge. I must have warped it while trying to remove it. I ended up popping off the shell again trying to take it off the Clear frame.
That actually made it easier to "curve" the icon so that it would remain flush with the earstem. Thankfully, the shell stuck back onto the substrate. I hope it stays that way.
After that, it was pretty straightforward. Here are the new Fatcats:
Crystal Clear/Grey with Gunmetal Icon
Matte Black/Bronze with Gold Icon
Now, back to the lens rattle. I tried a really simple and cheap solution: Elmer's white glue. Basically all that needs to be done is to fill up the extra space between the lens and the lens channel in the frame. I figured a bead of glue on the outer edge of the lens would do the job and be outside my field of view. White glue is also pretty harmless and shouldn't cause any permament damage if I need to get it off the frame or lenses. So far it seems to be working. I'll have to wait and see if it holds up under normal wear and tear.
That's it!