1953 was a transition year for the Chevrolet six. The Powerglide cars came with the first "modern" 235, with aluminum pistons, high pressure, insert rods, and the 18-bolt head, but still with the old 216-style valve cover. The standard transmission cars came with a 235 with the the babbit rods, low pressure oiling, cast iron pistons, but with an 18-bolt head, also with a 2-bolt valve cover. Both engines had the low side cover that did not cover the spark plug holes. I'm less sure about what the 1953 trucks had, but as I recall (and what the Master Parts Catalog indicates) the truks with 235s were like the 1953 standard transmission car engines. In the late fifties I had a 1953 standard transmission Chevy. When I replaced the babbit pounder with a 261 in 1958 I used the head from the 1953 235, which came from a 1954 235.
Thus a head from a 1953 235 will not readily fit a 216, as the 216s were all 15-bolt heads. I have heard of people that have modified a 15-bolt Wayne 12-port head to fit a late 235-261 18-bolt block, but I'm not sure if one can go the other way.
There is a link to the 1929-57 Master Parts Catalog in the Links section of this great site.
Hoyt
