327 xd suffix

I have a 1965 327 race engine I took out of a 1948 Sprint car. the block has a casting of 3782870 and a date cast of A255. The heads are 3782461 double hump heads. They are 1962 cast dates. it has a 57 chevy edelbrock intake with 3 ford deuces. The stamp on the engine is a F0128 XD. I cannot...