Ok, I broke the Rail on my 91 Sovereign 4.0. I had an out of town salvage yard mail me a used replacement from a 92' XJ40, assuming they are the same from 90'-92'.
1. The 92' injectors fit within the intake just fine (I attached new O Rings), but the tips of the injectors are different. The injectors from my 91' are 1/4 longer than the 92's. The nozzle-spray tips have a single outlet, the 92's have a 2 holes at the tip... This may work just fine, I don't know, but the issue is...

2. The alignment at the front end of the Rail does not line up with the connector to the FPR. See pics

So my question is this rail compatible with my 91'... and if so what am I missing here? Injectors compatible? etc...

All help appreciated...

 

Im glad you could get one. The injectors with the green stripe are for 93 and 94. As far as I know the rail itself is compatible. I hope someone will say so if I am wrong. I tried swapping a set of those into my 92 and it set the engine light off. Good luck.

 

That sounds correct, I'm definitely not gonna use the injectors, then....

But the fact that the rail is not aligning with the FPR is baffling. I looks identical at-a-glance. But the issue is the connector at the FPR which is broken off on the old rail I'm replacing, so I can't truly tell if the rails are EXACTLY the same.

Any other input our there?

 

As it happens, I was just tinkering with my 94 this week. I swapped the FPR for a known spare and found that I had to loosen the rails' mount bolts to get the flare nuts to thread. I cranked them tight and then tightening the mount bolts seemed to make it all line up. Also, you can compare part numbers at the Jaguar Heritage Parts site to remove all doubt. BTW, my problem turned out to be a bad Coil Wire- so you're not alone! Good luck.