I’m only just facing up to the fact that a car built in 1997 still has a mix of metric and imperial fastners. Is the rear shock bottom bolt metric? The front ones appear to be imperial.
I think X300 is fully metric, which means imperial tools will fit the common 11mm. 13mm sizea and others.
The nuts on the diff output shafts are 11/16"!!!
The nuts have been that way since 1961 when the 'E’Type was introduced!!!
All Salisbury and DANA diffs (The 4HU, 14HU and 15HU used the 11/16" nuts to hold the 'U’Joint flange to the camber spacer/output flange.) use the Imperial nuts.
The last Jaguar to use British Standard/Whitworth was the XJ40 on the battery terminal connectors. (maybe the XJS has the same 1/4 Whit/5/16 BS battery connectors??? I don’t remember)
Pretty much ALL the other fasteners are METRIC.
I have a 50 year collection of tools to prove it.