OK thanks to Wolf's work I think it is clear that the Kuberol car (the S) was NOT a customer M491 car from this list but likely to be a kit car built up on car made earlier than the 72MY.
Based on the same reasoning I think that THIS one below for Gunter Schulte for Hulpert racing team at the Norisring is may also be a "kit car" and not a customer M491 car.
Attachment 406289
However this one below from the same race is almost certain to be the Krizella car 0934 looking more like tangerine than the colour in the photos I posted earlier when it is in the USA
Attachment 406291
THIS one below for Jean-Pierre Jabouille at the EC GT race a Paris in April 1972 looks like a real one that I have not been able to identify so far.
Attachment 406290
The fact that PORSCHE is shown as the sponsor is more evidence. This MAY be the one car that went to France according to one of the sources.
These other ones below are also almost certainly "kit cars"
car #293 Hasselbecker racing team
Attachment 406292
car #20 Nirvelles Hans-Peter Joisten
Attachment 406293
Finally I dont think this is one for Kinnunen at the 1972 Arctic rally is a customer M491 car either although it is a definite 72 and entered as a Group 4 car. A clearer picture may help.
Attachment 406294
however given that 16 of the 21 cars were originally identified above and it looks like another 2 have been in the thread so far, the Spanish rally car and the Jean-Paul Jabouille car (so long as it was not one of the ones previously identified) that makes it 18 out of 21.