Aye, I remember the fascination of punching some of my old cars to watch the gas gauge go down.

I had a 68 Cutlass with a built 396, I forget the heads but it had the 510/320 cam like the RA II and IV, it got 5mpg, the car was unreal, someone else had built it and it was one of hose local cars with a reputation that as a kid you bought because of that, if I hadn't spun the #8 rod bearing I probably would have killed myself in it