Yes, the original cars had the vent from the MK III Ford Zephyr. There are two types of vent out there, the one from the later '65, '66 Zephyr has an upward curve at the front leading edge and does not fit as well. I have two of the flat grilles sitting in my shed. One is for my car (naturally) but I am willing to sell the second one. email me if you are interested and we can discuss price. The last ones I sent to the UK were £25-30 (depending on condition), including post and packing. I believe Robert Logan from RF has had a pattern made to reproduce these grilles, so it may be worthwhile contacting him.
Cheers, Brian.
