Owners manual?
USUALLY, one will find a free pdf download for an owners manual for nearly any Kymco scooter, motorcycle or mobility chair. I did not know they even made a 125 motorcycle! Added to the large amount I don't know! There are not too many places to hide anything on a motor bike so my first guess would be to remove the seat. That is if the fuse block not in some convenient snap latch compartment.