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.
Great copy of the manual, has all information required for servicing,
Text excerpt from page 1 (click to view)
DVD RECEIVER AMP
MM-DS80M
CHANGE NOTES. 1. DVD-PACK Specification is changed .
SERVICE
DVD RECEIVER AMP
SUPPLEMENT-1
Manual
Supplement to the Service Manual MM-DS80M
This supplement contains change notes differing from the Service Manual MM-DS80M use both this supplement and the Service Manual part number AH68-01383G CONTENTS 1. Electrical Parts List 2. Block Diagrams 3. Schematic Diagrams 4. Troubleshooting