I know this is a late response. You basically need a male 3 prong plug with 2 connectors branching off of it. the positive will go to both connectors. one being low beam and other being the high beam. now the ground from the main harness will only go to the low beam. the high beam ground, you ground to the chassis. This allows flashing to pass.

If you need more info, Just PM me. this was a basic writeup.