My method: Wet multiple pieces of thick paper towels in mineral spirits, enough to cover the circumference of the rim, keep them connected to one another. Also lay out a long strip of plastic wrap on the floor. Again, enough to cover the circumference of the rim. The paper towels don't need to be dripping wet. I twist the paper towels loosely to make a sort of solvent rope and set it in the tire channel around the rim. Then put the rim plus solvent-rope on top of the plastic wrap. You could also lay out the length of paper towels on the plastic wrap and roll the rim on if you prefer. Anyway, run some tape around the rim between the spokes to hold the wrap and "rope" in place, then tightly wrap the rim in the plastic wrap to hold the paper towels in place. Wrap some more masking tape or whatever around a few other sections of to seal it all up some. After soaking for an hour or two the glue should wipe right off with very little coaxing.