TRX- I checked there but didn't find a place where they had the float valves for sale.
Don't listen to quad, the only thing he can help you on is how to drink beer...........really fast!
There is a guy that goes by the name of Dr.Q. He specializes in 500's and know his stuff. That and there's a website that is for quadracers and zillas only. Some good info there.
http://s15.invisionfree.com/LT250_LT500HQ/index.php