Upper Dash Pad Question, What have people used as padding under new vinyl? Options

[ehokana]

Hey guys

I have started working on getting my car back together and decided to get the dash reupholstered to match the rest of the interior. Anyway, I pulled the vinyl on the upper dash off so that it could be matching as well, and some of the foam-type padding came up and tore- not exactly unexpected for 40 year old foam. I spent tonight cleaning the glue off of the upper dash (what a job that was) so that I could glue the new piece down once I get it back from the upholstery shop.

So, to my question, what have people used to replace the foam padding under the vinyl when you replaced the upper dash pad? I thought about just gluing the new piece of vinyl directly without any padding to back it (because vinyl now is significantly thicker than what was used on the upper dash originally) but I'm afraid that every little bump on the dash will eventually show as a dimple on the vinyl. Does anyone have suggestions or something that has worked for them?