Probably it never existed a 1081 official service manual from Commodore, it's look more like a NAPCEC service manual & diagrams compilation of the 1084 series and his variants, like the nap6523, 8cm505, 1084S, 1084P and obviously the 1081. It's more complete than other scans and the quality of the scans also are far superior. It has two circuit diagrams variants of the 1081, mono and stereo versions. It doesn't include a diagram for the Philips CM8500 or CM8501, they look like the 1081 but they are slightly different.
Text excerpt from page 43 (click to view)
DV-K301C
KRJB ASSY
FRONT PANEL SECTION
Main Cam
Note: The loading tray can be pulled out when the main cam is in this position. (The Lock Lever should be in the notch of the Main Cam.)
1 Fitting Lock Lever
1 1 Rear Panel 1 1 �2
1
Nyron Rivet 4 Cutting Pliers 2 �4 2 5
4 KRJB Assy
3 Release two Binders. 3 �3 Unhook 6
Tray Panel
5 Remove PW Joint and Power Button (RL type only) Power Button