You're talking about that crap in the back seat insets? Or the crappy stuff they put on the supreme front doors that has black strip in-between?
Either way, there's got to be a better way. That stuff couldn't take the heat and either wrinkled up and fell off or turned black and splotchy. I guess if you had it in a perfectly controlled environment it may do well, but otherwise...
I'm not sure of a suitable remedy for said junky parts.