I also had to do the same for my IVA. If you send a letter to ford with your engine number (located on the exhaust side, on the crankshaft end).
They will get back to you reasonably quickly with the engine age and some technical data whilst mentioning your serial number.
The template for the letter and the address is shown in this thread:
http://www.locostbuilders.co.uk/view...php?tid=170718