The numbers you gave are for the intake manifold and the water pump, on an engine of that vintage they don't mean much for determining what the engine itself is.... Can you get the casting number off the block? I believe on the FE engines it is above the starter.... Even that on engine from this year is not necessarily exact to say what it is. Then there's the fact that over the years, most anything could have been swapped into it during an overhaul or rebuild. Decoding FE's is not an exact science!!!!!