Ok I installed both LL and no power. I disconnected the front and hooked the speakers direct and the amp came back on. Reinstalled the LL no power to the amp. Then I remembered that I now have a flat input so I needed the remote wire hooked up. As I looked for a place to hook the remote (cig lighter). I researched the schematic and found the remote wire out of the radio. Well low and behold......power to the amp. I'm not sure if all boom box has this but the 2018 does. I always ran the remote wire to the cig lighter if it was needed. With newer amps having low volt auto on, a remote wire isn't needed. With the LL's it is needed. The only thing I didn't like at first was with that remote wire, It wont turn on in ACC mode. After thinking about it, that's a good thing to keep from draining the battery. An old dog is learning this boom box stuff.

BTW tuning the amp I ran the bike for 15 min or so and adjusted the gain to some hip hop pounding bass (not my usual listening music) so not to clip out the channels but right at the edge.

 

HD part #6920921 is a y adapter that will work better for a turn on. Acc will work after installing it. $10 at the dealer.