Well, typical of me to go round the houses when trying to sort a problem rather than to go straight to the source.
Having decided on Pirelli PZero's for the rear of my daughters car I found that Kwick Fit online were selling them for £194 with a load index value of 96. This started me off on a bit of a tangent to find out what this meant and was this index suitable for my daughters car. Well after much research ringing Kwick Fit, the local Nissan main dealer, Nissan Customer services, Nissans Nismo branch in Scotland and Pirelli themselves. No one had any idea if the 96 index was suitable nor did they know how to calculate if it would be OK.
By the way Pirelli even suggested that the PZero has only been tested for the Jag XF suggesting that if you fit it they won't be responsible. I said that every tyre shop in the NE and I suspect the country are selling them to any car owner out there, their response , well that's up to them, giving the impression that should anything go wrong they will stand by our claim that it's only been tested for the Jag? Couldn't believe any of it.
Anyway after all this grief all I needed to do was to look at my daughters car book to find out that 96 is their recommended rating. No wonder my school reports always said " must try harder"