I installed the Evo one and the Maz 3 harness, and all works fine. I spliced into the light switch, labeled "optional", and the parking lights come on as expected when in auto start. But now I see a connection at A19 of the white connector that seems to duplicate the same parking light output. So why was the light switch tap and splice labeled "optional"? Could I have avoided this light switch tap and splice if it's already made at A19? The switch taps and splices are the most difficult part of the install with the Maz3 harness, so what is optional about it?