Thanks to this service manual I repaired my old camcorder! The manual perfectly explains how to disassemble the camcorder step by step.
Text excerpt from page 19 (click to view)
6. PRECAUTIONS FOR REPAIR: MODULE QW-1553 / 1554 6-1. AC (ALL CLEAR) AND REMOVING OF MODULE
1.Perform AC (ALL CLEAR) when inserting a new battery, or else the memories and/ or counters may give erratic displays. Touch the AC contact and the positive (+) side of the battery or main plate with the metalic tweezers. The contact should be made for about two seconds. 2.On removing of the module from the case, please insert the precision screw driver between the module and the case pointed by arrows. 3.After the AC operation, "OPEN" display may appears on LCD. It means the back cover is opened. 15 seconds has passed after the back cover is closed, "WAIT" display may appears on LCD. It means the data is checked.