Unique Issue; Rear drum and Rim

[Burlandofam]

Correction; 1971 D20 chassis.
Issue; Previous owner put on non factory rims (singles) backwards. These rims have a small ridge to contact the drum on the inner side of the rims, the outer side is totally flat, so the contact patch of the rim,  instead of being 1/4 inch wide, is now 1" wide.  More surface area rusted to the drum and thats not the only thing...the lug nuts, and consequently, the holes on the rim are both tapered.  Possibly, he deflected the metal of the rim surrounding each stud inward when tightening the lug nuts, making it virtually impossible to remove (with the exception of having a "way-back machine"). Soaked all possible rust areas with PB blaster for 2 consecutive nights and sledged the rear side of the rim with a sledge on a 4x4 oak plank.. nothing.  Took an 8' 4x4 and chained it through the vent holes on the rim, getting the end of the 4x4 as close to the rim as possible at 3 oclock. I was able to use the full floater axle housing as the fulcrum, and snapped the welded chain. The tire is flat ( slow leak was why I looked at it in the first place, and the D20 is in a storage yard without power to run my compressor to air it up. I feel screwed, but am wondering just how screwed am I and what can I do from this point before I cause other problems with the rear brakes et al?
Thanks in advance.