David, That’s interesting and I imagine pretty damn frustrating. I’m just coming to end of my 420R build, hopefully. I still have a few bits to complete which are taking me longer than expected (spent all day fitting rear wings and day before doing front wings, all quite fiddly and time consuming). As per your comments, I have relied on downloaded manuals, (‘Old’ 2015 guide and IKEA version from website), plus Derek who has been good, and the many blogs that various people have kindly produced and existing BC forum posts. Currently I have arranged for Caterham to pick up my car on 8th July for PBC, although I am getting a bit nervous about completing everything for this date. If you have any other items that relate to incorrect instructions in manual I would be keen to know what they are. Good luck with arguing your case, it seems pretty strong to me. Tony