Dylan, the OEM filters are still available from Toyota, but a generic one can be used if you need something easier. The fuel tank comes out when you take out the seat, fuel tank cover plate, disconnect the level sensor wire, disconnect the fuel hoses.
The fuel return line is for the Aisan carb, you will want to plug it or remove it and plug the fitting on the tank if you're set on using the Weber and the Weber doesn't require it.
The fuel return line is for the Aisan carb, you will want to plug it or remove it and plug the fitting on the tank if you're set on using the Weber and the Weber doesn't require it.