Got my poly body mount kit the other day, and I'm having a little issue. Well, the very back mount on my blazer is that weird looking flat rectangle one, not round cylinders like the rest. Why didn't my mount kit come with one like that? Also, that rear mount is stuck on the frame, do I just scrape it off? Or, does the new mount kit come with replacements that don't look the same as the stock ones? Noob question I know, but it had to be asked.