Need help wiring Yamaha Portasound PS-3

[hyaki]

Hi guys,
Me again yet having another problem 
I got this Yamaha Portasound PS-3 from a friend, he said he was trying to fix it because it has crackling sound out from the speaker. What he do is desoldered the jumper wires that is went across power board, main board, battery etc without marking or documenting which wire should go to which point. So he lost it... he forgot completely.. (dumb ass!!)
So now I'm trying to help him out, connecting wires by matching it's ID that is written on the board.
But, I found that is more wire than the points...  I got confused!!
So anyone who has a working Yamaha Portasound PS-3, would you share those wiring schematics for me?

Super Thanks