The Stovebolt Site Forums The Shop Area Engine Shop what year 235 to look for??

I took a short water pump and pulley off a 47 1 1/2 ton in a junkyard that had a later 235 that looked factory,that truck had been in there many years and before all the shortened pumps and adapter came on the market. I have seen a couple more that looked like it had the same pump so i am wondering if GM made a short pump after the 55 motors came in production to install in the earlier trucks,I have no parts manuals that I can check it out but that truck probably had been sitting in that yard since the 60s.