Hey Tony,
THat may have been me. A guy at my work bought something called Flexane, manufactured by Devcon. It's a two-part system, once you mix it you have (5 ?) minutes before it cures. Ends up a tough, flexible, rubber-like consistency. He mad a boot for a hydrophone/cable assembly by turning a 2-piece wooden form on a lathe. When it was cured, he removed the outer form, cut through the rubber w/ a razor blade, removed the inner form, and then re-glued the rubber. I haven't heard how it worked "in the field", but it looked pretty nice. I think that stength-wise it would be great for anything automotive, except maybe bellow-type parts that have to flex a whole lot - it
might be a little stiff for that.
He bought the stuff at Grainger.com; they are kind of snooty about selling to businesses only, so be ready to deal with that or shop around. I'm sure someone else carries it.
Ayway, the guy poured the excess into a puddle, which I kept. Here's a pic :
