I replaced the fuel tank on the drivers side because it was leaking and fuel gauge was not working so I changed it too. I ran the truck on each tank and they ran well. Now that I try to run on the drivers side I get water in fuel light and it runs rough. Switch back to the right runs great and no light.. After hours of trying to get it running on the left tank, I decided to check for fuel pressure. When I took off the cap, fuel came gushing out of filler neck. Must have been a lot of pressure for sure. Lines hooked up the same. I'm Baffled . First time 60 years. Help! Please!