Product review (5 stars): DIY repair fixed dryer and no more burnt collars!
Big hint: Use nail polish remover to remove the old glue if you're replacing dryer felt.  Sandpaper takes hours and a million gallons of elbow grease.

There's a youtube channel for DIY appliance repairs that is awesome: search youtube for Replace Rear Dryer Drum Felt Seal.  These how-to guides are outstanding!  The 2-day free shipping (thanks Amazon Prime!) sealed the deal, so I bought the part here.  Using the youtube video, and the nail polish remover tip from a local hardware store (they told me to try it when I was buying sand paper), I was able to remove the drum, remove the old seal, remove the old glue, install the new part, and now the dryer is good as new.  No more burnt/stained collar tips!

Clothes seem to dry a bit faster, but that could be a placebo effect.  I didn't time a before & after.