At the time I didn't like the idea of exposed holes and wanted a cleaner look, thought the carpet would stick to this better, also looking to make it more structually sound for T top, rember these cars were only worth 4k then, no one would spend 20k doing rust repairs, cars sales I bought it off used spray foam, and pop rivets and steel road signs with layers of bog to cover up with, that's how things were done then. Car racing mob next door remarked about was a Datsun really worth all tne work I was doing.