Whilst this is a photo copy, and some of the pages are a little askew, it was all readable and intact. A real bonus finding an old manual for a classic piece of kit that no other site had.
Text excerpt from page 5 (click to view)
4. NOTE ON MOUNTEING SLED MOTOR
1) 2) Push the sled motor assy 1 toward direction A. (See Fig.5) Tighten two screws 2 (M1.7 Ã 2.5).
1 Sled motor assây
2 Two screws (M1.7 Ã 2.5)
3) Raising the MD block assy 3 90 Âº with the side down. confirm that the optical pick-up 4 falls by self weight. (See Fig. 6) Further, with the front side of MD block assy 3 up, confirm that the optical pick-up falls by self weight.