The positive [5 VDC] from the Light_it was connected to the red positive of the HMA Flashers which are arranged in pairs left/right-ha side.
The decoder was connected for testing on its loco address of #3 and using programming on the main [POM] the relevant CV's 137/138 were set to effect 9 for a Phase A.
The user has a choice of DC / DCC for operation and in DCC can use a loco or accessory address. When using an accessory address, additionally have the option of syncing the flasher lights using a combination of option 9 / 10.
The simplest way to operate these would be to use DC and a BOD20 or other device to apply the power across the Light-It connection. This project is for a customer and will feature full flashing lights/gate operation and sound controlled using an NCE Mini Panel.