I'm in the process of replacing the headlight lens on my 99 XKR. Unfortunately I have dropped and lost the T40 Torx screw that secures the unit underneath.
The part No. is JZS100139. Jaguar no longer keep this part. Anybody know of an alternative or the thread type and size. Many thanks

 

If any standard auto part store can't help you buy a T40 screw, then the way I see it is you have two options. 1) Find an independent shop that works on Jaguars and see if they have any on hand. 2) Google a fastener supply warehouse and see if there is one nearby. I had a TR3 that needed front wheel bearings years ago and no auto parts store carried them. I found a bearing supply warehouse and took the old bearing with me and they had exactly what I needed. You've lost the Torx screw, but the fastener warehouse may be able to cross reference. If they cannot, there's only a very small handful of thread sizes, maybe 3 if that many, for a T40 screw. Buy one of each and call it a day. I can't see them costing more than $1.00 each....it's just a screw.

 

I found an old Jaguar technical bulletin for an upgrade to stop a rattle in the XK8 interior that used the same screw and a M8 nut. Went to the local hardware store and got a M8 bolt which fits perfectly.