Back in the days of AMC / JEEP of course AMC sold JEEPS . The AMC 258 straight 6 & the 304 & 360 V8 engines were used in both AMC cars & JEEP vehicles . The parts department had an AMC book & a JEEP book . The exact same part was quite a bit more expensive in the JEEP book than it was in the AMC car book . I lost track by the time Chrysler took over Jeep but I wouldn’t be surprised if the practice continued .
I’ve never heard of a dealer using a multiplier system so I certainly would not tarnish them all because of that one.
My sample size is the 5 I worked for and others where I had friends employed with war stories beings swapped about service department procedures and so on.
I have seen labor procedures listed in the book which might state 1.0 hours for a certain repair. Add .4 for A/C or .5 for this or that all depending but that’s a published labor guide; not some kind of dealer cheat sheet which they typed up.