You can find the engine manual in this thread,
https://www.6post.com/forums/showthread.php?t=803495
If the person doing the PPI is a already familiar with BMW's they likely won't need this but if they are a general mechanic this could be good prep material before making the inspection.
The vacuum operated exhaust valves is something else to get a peak at while they are looking at the rear diff. Some folks pull the vacuum line off and wire em open with coat hangers. Some folks like them open for the warm up and some folks do it because they start rattling after they age. Whatever the situation you'll want to know if the resonator is factory and if the valves work.
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2015 F06 M6 Silverstone Metallic II, Individual Full Leather, B&O, Night Vis, CCB, RKAutowerks (CP Rods/Pistons, DI Cams, CF Intakes, Coated DP's & Billet Diff Brace), InfinityAuto Turbo Inlets, Mishi Oil Cooler, JB4, XHP S3, BM S3