Rookie question regarding spar

I would also check the tie down ring for the tail at frame J, those wrinkles could be from a "tug" while the tail was secured.

the stress of a sudden stop could be tail parts forcing a twist. However to me the pics look more like pressure push on the lower right. Dry ice may pull some of that out. It would take some careful measuring from the trailing edge of the walk box to the front of the rudder to find twisting.

Still looking at buying this Ercoupe, and it has some wrinkles in the fuselage. The spar is allegedly in solid condition as verified during the last annual, seller's representative does not know what caused the wrinkles in the skin. My question is how can I tell if the spar is in good shape? What does that look like? Two pics of the fuselage wrinkles in case that brings up another issue.

Thanks in advance!

W