Completed assembly of the tank top skin as well as install of the tank return line with clips and bulkhead/sender plate. Took longer than expected, but seals all look very good for all seams and rivets/screws. Fit of the fuel return line also seems very good.
Will wait for about a week until sealant is cured before testing the tank with balloon for leaks.
Completed, sealed fuel tank
Bulkhead fitting and sender plate sealed into tank