My rear panels purchased from Classic Industries have extra material on the top, bottom and front side...what is that all about? Do I trim, fold under, tuck somewhere??? Thanks.

Yes!!! ;) All of the above. Trim, tuck, glue, fold etc.... until they look and fit like the originals.

You need to reuse your original metal upper pieces. The extra material on top is glued to the metal pieces, and then the inner fuzzies are stapled to the metal lip.

Unreal, I don't quite understand. Inner fuzzies? I have saved and will reuse the chrome top retainers, but didn't get the rest.

On '68s and '69s the door panels extend up and over the inside of the door frame and have a place to mount the inner window fuzzy.

I take it from your displayed name that you have a '67?? Disregard Unreals's info about saving the metal and fuzzies etc... Your door panels don't run as high as ours, they stop a couple inches below the glass!

The extra material is to cover any areas that need it. Trim off the rest to look like the originals

You are right PDQ, I was describing 68-69. Sorry for the confusion.