Yep, afraid you do have to remove the center support to get the cork on. Here is a picture that should show it pretty clearly. A little liquid dishwashing soap works wonders on the rubber to metal contacts.
http://www.pbase.com/dennygraham/image/121008098/large Thanks for the FelPro part numbers, I'll add that to my folder. I'm surprised that NAPA had them but that's a good tip, the price is the same as the catalog vendors but they tap you for another ten bucks S&H.
Denny Graham
Sandwich, IL