Get some upholstery and redo them if the foam is bad get new foam the rear seats won't need foam at least mine didn't I only needed drivers seat foam and sitting in it now you can definitely tell the difference.
Looks sweet man, looks like a good project. How about some leather covered stockers? I'd like to do that one day. Or just clean stock seats. But that's me, I like to keep the interior clean. Keep up the good work.