I would drain the tank to see if the filter is clogged and if so clean it. I would also disconnect the line going to the fuel pump and blow air through it to clean it out. If the tank is full of crud it should be removed and cleaned or replaced. Once that is done you can determine if the fuel pump needs to be replaced. This is what I did on my 76 Vette though it had sat for a couple of years and the tank was full of crud and the fuel line to the pump was partially clogged.