Well, that turned out better than I thought it would.
Band-sawed the rubber pieces with a super-fine blade and it worked!
Only had to do the two end pieces (because these pieces are jointed and relieved at the corners where they bend) that actually contact the sides of the radiator's tanks, while leaving the center part (that contacts the top and bottom) stock thickness.
Quickly learned that it's not good enough to just support the sides of a piece of rubber being shoved through a band saw, but after it is separated it tries to go down the 'rat-hole' where the blade comes down.
Put a thin piece of plywood under the rubber and cut it at the same time.
Bingo. And I didn't even lose the end of a finger!
Mac.
