Question on Mustang fiberglass floor pan

Thanks Tim.I am going to leave the 1/2" floor that I have on there now after I remove the carpet from it. The reason I ask is because if you look at the bottom side of the back panel,you can see where 1/3 of it by the exhaust cut outs looks like it had something bonded and the rear of the panel had what looks to be a 6 x 14" piece. I think I will do the aft panel the same as the kickboard.

Started working on my floor pan yersteday and I have a question for those who have had theirs out. The toe board is backed by plywood bonded to the glass.Naturally it's all rotted so I am replacing. But the panel that goes from under the motorbox to under the back seat was missing most of the wood. Am I correct to assume that this panel like the toe board needs to be completly backed up with wood? I'm thinking it does but want to check. Thanks