Oil pick up pipe seal failure perhaps? There was a service bulletin for the early cars I believe?
"TB0037 Issue 2 Release date 19-10-2001
Title: Tappet Noise- Air leak at oil pick-up oring.
Description: Tappet noise on cold start or when engine idling.
Affected: All vehicles with KV6 engine
20K ***** 168295
25K ***** 168506"
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https://the75andztclub.co.uk/forum/s...ad.php?t=64237