If you just run the one tank, it is simpler... there are still three small tubes in addition to the big filler hose. One of these three small hoses will be bigger than the others -- that's the pressure supply line from the in-tank fuel pump... connect that one to the tank side of your fuel filter. The other two small lines should be about the same size; connect one to the return side of the fuel pressure regulator and the other to the charcoal canister hose.

You'll still need to figure out which two wires feed the fuel pump (see above) and connect those to yourstock fuel pump electronics. You'll need to sort out any other wires (see above) and hopefully get the feul level sender to work with your guage. Check the values in a factory service manual -- I bet you'll be able to use the Isuzu sender with the Toyota instrument panel.

Randii