Over or Under?

[AZKen]

1960 GMC: Did the factory put the rubber mat under the firewall cover or over it? What is best to do with the available aftermarket mat and firewall pad/cover?

[jbgroby]

Logic dictates it would be over the pad as the rubber would protect the cardboard from water damage.

[AZKen]

Water damage? From shoes? Maybe I didn't ask this the right way.