Convertible roof – Pre-facelift and Facelift differences

Hi,

My question is – is there a difference between the mechanism on a pre-facelift XJS Convertible and one from a later Facelift convertible

My 1990 convertible is a sort of hybrid, having parts from the pre-facelift while the majority is Facelift – when I bought it had the older style chrome bumpers rather than the plastic wrap around Facelift, even though the rear lights etc were Facelift.

To my point, my convertible’s roof has a bow in it, across the rear window. It appears that the metal bar(s) that run across just at the top are bent (how I don’t know). So if you were looking at it from the rear, you’d see that the roof itself is not parallel with the top of the window glass.

I’m therefore thinking I had better replace the mechanism with one from a scrap yard at the same time I get the roof recovered.