I don't have the CD, was only looking at the overview. One thing you can count on though, the 126 chasis (basically all chasis #'s) remain fairly static through their run. It is almost certain that the wiring for the cigarette lighter is unchanged from 81 to 88 (and probably to the final run).
As the production of a given chasis evolves there may be a few changes, but for the most part things stay the same.
And as you point out, according to the overview the 300SE only starts in 88. What is the production date of your car? It should be stamped in the placard on the driver's door pilar. (note, my 108 is registered as a 73 but was built in 72 - try finding parts for a 1973 W108 [they don't exist])
'73 280SEL 4.5 (9/72)- RIP
Only 8,173 units built from 5/71 thru 11/72
'02 CLK320 Cabriolet - wifey's mid-life crisis
2012 VW Jetta Sportwagon TDI...at least its a diesel
Non illegitemae carborundum.