1965 barracuda spare tire cover question

Its a plywood, maybe 5/8 thick and the "S" option had a routed out relief for the fatter tire. Id check thickness but Im out the door for work. ITs the same well for all, just a different top. There is an ad that shows all the "S" option special parts and the devider is one of them along with shocks, leafs, tach, etc.