GM pumps go out. The one thing I highly highly recommend is getting the actual GM pump. I put a napa pump in my dads truck and completely regret it. If it gets really hot and you drive it for like an hour now the truck shuts off because the pump cant take the heat. Get the GM pump, they cost more but its not worth being stranded on the side of the road.

Also, you sure you can get to it from the top? My 4runner had a plate ontop of the tank to get to pump without dropping the tank.
Prob not, but just an idea because I know how much fun it is to drop that tank.