I have just found me a 1966 c10 or k10 ? short stepside and I can not find vin on driver door like my two 1967s , or Figure out what inline 6 i have 235 250 or 292 it has fuel pump in the front, 1bb rochester mono jet carb, And coil right behind the distributor with aftermarket tall valve cover so thats what it making it hard to figure out b/c 292 had tall valve covers but aftermark addons make it harder to find out. Spark Plugs are Bosch W8CC 7504 plugs. Anyone Know This Please Help