The guy on Ebay that makes and sells these has them available again if any of you guys are looking for one, just a heads up.
https://www.ebay.com/itm/1971-1972-1973-71-72-73-MUSTANG-BOSS-351-MACH-COUGAR-BATTERY-TRAY-APRON-SUPPORT/323712441615?hash=item4b5ec3dd0f:g:CfsAAOSwPF9cdgPF:rk:1:pf:1