I use Juno Trak 12 instead of the Ambience. The track is more but the labor is way less. 12-2 Rx to each local tie into end of trak connector screw track to cabinet snap in heads and you are done. No special wire or cutting cover to fit the heads can be move or changed. I have tried to add to older ambience and when that cable gets hard the heads will not pierce the cable. That said I would still use the 12 wire for your application.
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