I did mine yesterday and maybe i was just lucky. I placed a trolley jack under the tank and lifted it into place to locate the fuel filler hose, placed a bolt loosely at the front to take the weight, then moved the jack towards the rear of the tank and just jacked it up and the hose slid easily over the spigot.
I did use the POR15 tank repair kit from Frosts auto to prep my new tank as my last one rusted out and caused me no end of problems blocking up filters. Hopefully this will now be a fit n'forget solution.
Nigel