Mikael I see you are facing a major challenge here. Let me suggest the following perhaps it can be of help?
Buy a few meter of this material, cut it to your satisfaction and stick a few magnets on top of it.
Vinyl with padding
PANTERA INTERNATIONAL
A DE TOMASO CAR CLUB
Presents the De Tomaso Forums
The On-Line Meeting Place for De Tomaso Owners and Enthusiasts From Around the World
Clicking on the banner will take you to the sponsor's website.