I wa just wondering because those 2 years seem to difficult to locate parts used, and many parts are not interchangeable with other years.
They will be getting rarer by the minute I’m afraid especially in the UK with the salted roads, something I notice is creeping into the culinary world with salted this and salted that 
I am in the us but I guess that doesn’t matter, the less ther are the higher the resale goes on mine.
The XJ40 with the 6 litre V12 are scarce. Even more scarce are the X300 ('95-'96) XJ12’s
They’re not common. Like you mentioned, there are several systems on the cars that are unique to those years, so I think that has resulted in a higher attrition rate.
It used to be that I could find a car in the junkyard to get parts from pretty easily, but even that is becoming difficult. Personally, I do hope this causes the values to rise some as it will help with aftermarket parts availability and I just have too much work and money in mine to think about how underwater I am on it!
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