If you wait till it is near empty, it will be a lot easier to handle. Support the tank with a board and jack. Disconnect the fill hose. Disconnect the sender wiring connector. Remove the nuts connected to the straps to the skid guard and lower it carefully. You will probably need someone to help steady it.
Just have a fire extinguisnher handy, don't forget you have gasoline and fumes to deal with. If you don't feel comfortable handling the tank with gas in it, take it to a mechanic.
Good luck,
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