OK, first off, I would not do that. Why you made a bet with a friend to do that is beyond me. I know Steve-O did it on Jackass, but that was a controlled environment with people knowing he was going to do it, and Steve-O is a complete idiot. I would not want to be known as "Poop Boy" for the rest of my life.
Secondly, I am sure you would get into a very large amount of trouble if you did it. That's not worth the $500 either.
Finally, if there are blades that would cut you up, then that means you could be killed. That is also not worth $500.
Someone I knew from school did the lay in the middle of the road thing from The Program for $6 and an ice cream cone. He was run over by a car and ended up with two broken arms; he was lucky.
Mark, do not do this.