The idea here is to take some measurements using a caliper to decide on some cuts. It looks like I will use the entire window sill from the PT Cruiser.

Similarly, I'm checking the rear for where to make the cuts. Because of the side body curve is so different, I need to just remove the roof for now and flex the sides to fit. That's my plan and I'm sticking to it.

I decided to cut along the body line that's already established. It's straight seam goes all the way to the rear of the PT but  left some fender as fill. Now, I can whittle away the PT's rear fender to match the Prowler.

I aligned the top of the Prowler door and PT seam. Then whittle away at the fender until it fit. I removed the posts and then chopped the "C" post 6mm. The posts need to be repositioned and no sense in chopping them through the middle. It's starting to look like the original plan.