So I did my duo headlight mod a while ago, with old cables from a charger, two end clips and electrical tape.
I modded it so high beams shines both headlights, but low beam cuts the circuit. (saves battery, no need for charger)
I had this setup for a year, never needed a charge. Battery still good

So flip the housing for the green side, so the green side positive is not connected (Put electrical tape if you wanna make it more safe, make sure its not exposed to touch anything metal )
then turn it backwards so that it is facing the opposite direct, so the positive green is facing bottom but the ground wire is still on same side
Grab your connector cable and put two end clips on both sides, then put one end clip in the positive terminal (yellow) ( I pushed it in and it hold pretty tight, better than splicing cables)
then put the other end on where the green + was suppose to be and electrical taped it securely.

AND BAM your done! no cutting wires, no soldering, no kickstarting needed or charging


Beware I did this on my Zuma 50 02 I dunno if 125 or 08+ models are the same
PS picture was from internet, was lazy to take pictures. but a lil visuals for u to understand
PPS Clips I used was two O clips, didnt have any others. If I had one that fit the terminal that be better, but not needed