Thanks, DavidG. Before going that restoration route, I decided to try "massaging" the seal. Here is a photo of the repop one I had. Sorry for the blurry pic; my camera was trying to "help" me by focusing on the driveway.
You can see the bumps top and bottom on the back, thinner edge, and the thick bump at the front before it turns up in the L. I sanded that off using a 1/2" Bandfile Belt Sander I picked up at Harbor Freight (Item#92158). Messy work, and it took about 45 minutes, being careful not to gouge the ridge that sticks up between the cowl and firewall (that's the only part visible). I flipped it over and sanded off both bottom bumps so it was essentially flat and very similar looking to my original.
After a quick wash to get the rubber grit off, and a dusting of Dri-Lube powder, it slipped into place just like the original.
