Can anyone provide the best way to install the filler neck when replacing the fuel tank? I had to drop the tank in order to remove. Then installed the new trying several positions attempting to install the filler through the floor. I am doing this on jack stands by myself. If this seems right maybe I will get a second pair of hands.

Its been a couple years since I did mine but I did it by myself. IIRC, I just pre-assembled the neck in place with the trunk boot slid down the neck so it would stay in place loosely. I installed a new neck/tank grommet in the tank and put tank up into place with strap nuts loosely screwed on. I then twisted the neck into the grommet. Some spray lithium grease or similar on grommet makes it slip in easier. Once its popped in place, I positioned the neck to body flange and gasket with the philips screws and then tightened up the tank straps and attached the trunk tube boot to the trunk floor. Hope this helps
Scott