91 Loyal stalling, Fuel injected

The last time it did this we figgered the gas gauge was wrong & topped tank off & it stopped. Now with the gauge showing 1/2 tank it's started again. It also doesn't like to start. Now a little history... Shortly after we got it I had to replace the fuel pump, because fuel was spurting out the little rubber nipple on the end of pump. Pull n save... After the stalling started I replaced the fuel filter also. When I pulled the hose off the output side the gas was clear. When I pulled it off the input side it was very orange. I didn't notice this when I did the fuel pump tho... I'm going to pull the filter hose again tomorrow & see what gas looks like. If it's orange I'm going to pull a hose at the pump & check it their also. I'm ASSSSSSUUmming the tank is rusty??? What kind if a job is it to replace a tank. THanks for your help guys. Jerry