When I picked up my '53 3600 the original 216 engine was knocking badly and since I had a rebuilt 235 on my engine stand, I went with that. This 235 has been a rock solid motor now for many years. Most use the adapter solving the low water pump issue, it's an easy swap for your 53. The perfect motor for my next build is a '55 first series 261, the very last high water pump motor and a bolt in, now just need more time and motivation.
Best of luck
