Dan (geckoracing1) has my 1988 mc18 parts book that has the case machining diagram, I don't believe the electrics are any different to the RS of the era '89 RS parts book here. The '89 F3 wiring diagram is identical as is much of the Japanese text regarding the setup of the stator, the RS book has it in English too

The '88 parts and '89 setup manuals are the ones that show up on Yahoo Japan frequently and cheap(ish)ly.
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