For those in need of rear vent seals. I found that 82 honda civic has a rear vent seal that is very close to the mavericks. They are larger than the mavericks but, all you need to do is cut them to size and put the seam at the front lower corner. You will want to cut the ends at a 45 degree angle you can use a black silicon to seal the seam.
Sorry I forgot I found them in the wrecking yard, much easier to find in good shape the Mavericks. Newer chevy car trunk seals look like they could work also, I used the Honda.
Thanks for the tip!! The ones on my '69.5 just crumble away when you touch them or open the rear windows.