GM's last 2 P&P's state that all supporting documentation (sublet bills, etc.),for warranty claims must be filed in the history file (1.6.3a). GM says they made the change for easier auditing. (Those auditors had it rough.)
The majority of dealerships attach supporting docs to the warranty copy or elsewhere. Not many dealers are complying with this policy. I don't blame them; the history file is no place for them.
The easiest way to comply would be to just keep your current filing system and just photocopy any applicable docs and add them to the history file (more paperwork-great).
Not too much of a pressing issue, but how is your dealership handling this?
Jay