I'm in the middle of adapting 98 sebring convertible seats to my 68 charger. My interior is black and the seats I got are white. I found a set of covers that I really like and I test fit them. I live how they look and I think they are "loose" enough to add some extra bolstering material. These seats are light years better than my stock 68 seats, but not as good as My 09 G8 seats. I know I'll never duplicate my G8 seats, but I figure while I'm doing this why not add some. I expect to put some sort of velcro underneath to get the cover to conform more to the added bolstering. I need some ideas for that, as well as what's the best foam to use. Also, these are covers that go over the original sebring leather seat covers so anything I put under has to have some way to adhere to the original leather. I'm open to any ideas.

Here is a pic of the cover test fit. I haven't cut holes for seatbelt or headrest yet as I still have to weld brackets to this seat.

I think those packaging wrinkles will come out and I have to paint that trim piece black, it's charcoal gray now.

I used spray trim adhesive to glue another 1/2 inch thick foam to my seat bottoms, but that was foam to foam, sounds like you want to leave the covers on and put more on top of the original covers, then cover all that with the new covers. I'm not sure how that will work.

I have to say, I am impressed with these covers. Even if my half baked idea of extra padding doesn't happen, I'm very happy with them. They are made by Iggees and they have covers for tons of applications.

Before pic of same seats.