I believe PHS has at times given out an engine unit number (or had them available for some cars), but I believed that was very rare. Are you sure that they gave you the Engine Unit No? I have the Car Billing History for my 68, and it has zeros in the Engine Unit No box. I also thought the number was a six digit number if I remember correctly. You are giving a 5 digit number for your engine unit number.

Is there a lot of engine paint causing the code/number to be hard to read? The dates for the engine/car sure seem corrrect!