Some of you may have seen this but its new to me. The engine block in my '51 is a 235 1956 Powerglide 0370817F56Y and a block casting number of 3837004 with a head from a 1953 Low pressure 235, head casting number 3701887. Are the two compatible? It runs rough and I'm trying to determine whether its fuel, spark, rocker adjustment or just parts that really don't work well together.
