I personally wouldnt want to just leave it there. I am assuming that you are talking about the head of the screw being stripped.A couple things you could try to do is if you have a die grinder, you could use it to cut a slot it the screw head to fit a large straight blade screw driver and try to unscrew it. Another option would be to drill the screw out. Sounds a little scary if you have never done it before but it is pretty easy. Take the one screw that you got out and find a drill bit that is ONE size bigger than the threaded part of the screw. If you have access to a drill press it is better because it will keep your bit straight but a hand drill will work. Drill into the center of the screw where the screwdriver would normally go. Nice easy slow pressure. Once you get through the head, the head should pop off and you should be able to pull the pump off the screw shaft. Then just use vice grips to remove the screw shaft. Hope this helps. Good luck.
