Big Pop:
If you checked your head # on Inliners, I believe they made a mistake. A 216 head will not work on a '50-up 235. The 235 went thru some changes in '50, including a new head design and repositioning of the head bolts. Other references show 3835499 as an early (54-55) 261 head. See the '54 parts manual
here (at the top of the page where it says 54 ALL w/261). Also see another casting # list
here. But there is still a problem. While a 261 head would probably work on a '53-up 235, I'm not sure it would work on a '51 235. There were more changes to the blocks and heads in '53, including the addition of three more head bolts, but I'm not sure if any of the original 15 bolts were moved. The 261 head
might bolt up, but some of the bolts would have had to be left out.
If you are sure the JAD serial number prefix is correct, I'd check the block casting number and casting date code. Also check the date code on the head. There would have been no 216 heads from '54-up, and no 261 heads from '53-down.
We have a bit of a mystery here!
