Interesting options. I’m wondering if newer heads would work on the 361. I believe, the problem with the engine is with a valve in the head. Engine shakes bad at idle, but smoothes out at speed. Engine doesn’t burn any oil. Engine runs very quiet also, (no rod or lifter noises) There is gas in the clean oil. (Could be the fuel pump). Just noting what I observed when I first looked at the car. I’m supposed to pick up the 59 coronet this weekend and the guy selling it assured me it would be running smoothly, but I’m not holding my breath.