Depends on how bad you want to avoid pulling the engine and ZF. I used to say there's NO WAY, until one owner with a severe rust problem sent me photos of his tank sitting on the ground with the engine in place. 'Course, the entire left side panel had been cut away for rust repair. A second owner chopped a hole in the firewall and pulled the tank thru there- again because of ongoing rust repairs.
Practically though, the engine and ZF should be removed, and that gives you a chance to address hidden rust problems in the corner behind the tank, and to cut away the rear crossmember under the engine and make it removable (along with the e-brake pivot bracket) like the Factory did in '75. Otherwise, the oil pan cannot be pulled without removing the engine. And one large water pipe cannot be removed intact with the powertrain in place. Opportunities....