Legendary vinyl top problem

The vinyl top is being put on as part of a body and paint job. I have known this guy for years, he has done other work for our family and has worked at a specialized muscle/classic car restoration shop.

The repaint was due to the grinding he did to get the adhesive off. I wondered why he didnt use a chemical remover but he aint the brightest light in the house... He also figured that maybe the clear he had used reacted with the adhesive, went soft or something, he has changed what he did for the roof so there shouldn't be a problem next time.