Has any one done this conversion using a flip open cap like those found on some Mustangs? I was thinking of doing this.

I think the Firebirds used an opening door. Check on a 69 bird tank and hardware.

69 Firebirds had the filler behind the plate like the Camaro. I thought that this other set up would be unique, and different.

My mistake, it's 67 & 68 Birds with the flip open gas door.