Regarding cabinets ;
The different manufacturers had different base colors that changed across the years. Back in the 60's and 70's Lead Based paint was used, and from what I understand a Gottlieb standard red was different from a Williams standard red. Then you have the finish, which again was different. Then there was webbing and or splatter.
For my restorations, I always find a section of the game that will have the factory colour and finish. Gottlieb red on Pro Football is exactly the same red on High Hand. The base on these two games was not off white, it was cream - exactly the same cream.
I never consult pantone charts etc. I have an expect match the exact color from the original game. I happily pay for the time spent to match the exact color with the exact factory finish.
Backglass ;
Very difficult as original colors rarely stay intact. I'm no expert, so hopefully someone can chime in and help you with that one !