Yeah, remember to use your camera you guys, I was stunned and wasn't thinking straight. Plus there were three of them and I thought they might fight me for my phone. And at 5'4" I'm not very intimidating.
After the fact I thought if I had grabbed my vicegrips laying on the floorboards I could have ripped out a valve stem...HA!
Thanks for the other tips though, I will follow through. I'll know tomorrow night whether I bid successfully for the ebay bumper.