removing 68 dart convertible rear panels?

If you mean the armrest panels...

Here is a link to photos I took while top replacement.
https://photos.app.goo.gl/soqZXhaUDYVyKc2v6

Remove the rear seat, bottom and back.

On the floor board there is a braket that screws into the armrests. And one that screws into the rear brace.

IMG_20200308_132847.jpg IMG_20200308_135110.jpg

I for got to mention that you need to remove the sill plates too.
20190505_151629~3.jpg