Excellent just what I needed to replace the electrolytic caps and make this old gem a beauty again. Was as scan of the original photocopied service manual.
Text excerpt from page 8 (click to view)
11.4. Disassembly and assembly of key(s) - Follow the (Step1)-(Step3) of item 11.1. - Follow the (Step1)-(Step3) of item 11.2. - Follow the (Step1) of item 11.3. [Fig. 4]
11.4.1. Disassembly (white keys)
(Step1) Insert the thin solid board between white key and black key, push the claw (refer to [Fig. 5] ).
(Step2) While pressing slightly the front of the key, push the rear of the key forward to disengage the key claw from the chassis (refer to [Fig. 5] ).