I would keep the 235 if I could get better carburation without having to go to multiple carbs or a 4 bbl intake,I have read that the 258 did come with a 2 bbl so thats what I would lke to find. I wish someone would have made a 2 bbl intake for those stovebolt sixes for one small 2 bbl carb,I am going to watch for a rusty AMC with a 258 that I could drive and get the feel for the motor before swapping it in the 37.