Underlayment confusion

Hey all, a bit confused here and need some guidance/ insight as to how things were done from factory.

I purchased a Repops Underlayment kit for the 68 Cougar, and am having trouble figuring out of the following two pieces are supposed to be placed:

I mean obviously the one on the right is for the driver side and the left is the passenger side but…

Do they go on top of or under the main Underlayment shown below? Or are they extra and not even supposed to be placed?

I would try to put the one piece underlayment sound deadner in first to see if it covers the whole front section from the left side to the right side. Notice at the bottom left corner of the 2nd picture there is enough cut out to mount the high beam switch to the floor on the drivers side., you’ll need to turn it over. Good luck and post some pics. John

The set I bought had a single page that defined where each piece goes. Maybe request that from the seller?