It is doable without pulling the engine, but complicated.
Do a search on oil pan gasket.
You may be able to leave the trans bolted to the engine, just pull the rear transmission mount and drive shaft, and use a jack to lower it, and another to lift the front of the engine at the crank pulley. You may have to loosen the motor mounts to get more clearance from the axle.
I've done one inframe oil pan. Small hands and the right tools to unbolt/re install the oil pickup tube.