I received my build record from Chrysler today, and the H is listed as:
H = 383-4 HP 8-Cylinder
Is this definitive proof that it was built with an HP motor, 325 horse?
If the letter H appears as the 5th digit in your VIN number then the car is an original 383 car. There`s also a pad on the engine block by the distributor that will have a letter to designate the year. H on the block pad would date the engine as 1972. Where are you getting the "H" from?