I dont say its the same everywhere in UK but from what I saw in the past, full service history means almost nothing to me. Even with lots of stamps on the service log book, I always find lots and lots of issues on UK based NSX. The front valve cover and the seal were not installed properly. ...
I think this WP is at the end of its life. Valve covers. Quite surprised with more gunk at the rear bank than the front one. With this blowby ...