I have rebuild the entire fuel sending unit with all new parts, gaskets etc. Had to buy each nut, bolt, gasket separately as the kit is no longer available. Problem is I have a constant leak between the sending unit and the tank itself. It appears the entire sending unit carefully fits into the opening but as see nothing that holds the sending unit tight to the tank. I am obviously missing something here. Any suggestions or recommendations would be very helpful and much appreciate. Than you.