While I'm waiting on Harmon to rebuild my brake booster, I might as well post the completion of the seat recover. The Clarks seats look great. The upholsterer I brought them to had a little bit of an issue with the passenger side front - a seam ripped while pulling over the frame/cushion, but they sewed it back and you can't tell.
Overall they look great.
The front seat cushions (purchased through Clarks) are not wide enough at the corners. The upholsterer had to add a decent amount of padding to get the wrinkles out.
Also, the buttons supplied kept separating and popping off of the metal piece. Clarks was apologetic and sent another batch of buttons - when they arrived there were two already separated, so I know it wasn't the installer's fault. Clarks is going to look into it, but my upholsterer superglued them back together and ran a thin bead of superglue around the seam of the ones that hadn't failed as a possible precaution.
Again, overall the product looks very good and makes the car look so much better.
Now I just need these brakes back together so I can drive this thing.