Does anyone know how to read these? I was told me the engine wasnt org to the truck when I bought it 2 wks ago (1964 C-30 6cyl 4sp) have narrowed it down to a 230 or 250. (Doesnt have the extra hose on the thermostat housing so its not a 292.) Here is the code located on the pad behind the distributor....F0526TAC No where can I find a TAC.....and if the C is extra...then the TA codes seem to be shared by both engines for different years(according to LMC Truck catalog). Anyone know how to tell them apart? Thanks