I keep the original (copies) from the MSA in the cars file, in the safe in our dungeon
and a 'Haynes' copy in the workshop for reference (ie covered in incriminating prints) I did have a copy in my briefcase in case I needed a quick check of anything whilst I was sourcing bits a while back !!!
I can honestly say theres not a huge demand for mine so I doubt I'm likely to make a mint from forgeries