I had a 250 six in a 72 gmc . My 54 has a 235 in it and I like the 235 much better.don't know what your 51 has in it or if it will bolt up to the 235, but I think it will .if you have a 216 I think the only mod for the 235 is a water pump with a shorter shafts. Or keep the stock 216.

Last edited by KEVINSKI; 10/05/2016 11:47 PM.
1954 Canadian GMC 9300
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