Be aware that the wiring harness for a Gauntlet is a series of 4 separate harnesses not including the control panel harness that you have.
There is a main PCB harness that connects from the power block/switching power supply/main board/sound board.
There is a sound board harness which connects directly from the speakers into the sound board.
There is a video harness that connects from the main board to the monitor.
The is a coin door harness which connects into the coin doors/main board/grounds to the power block/sound board.
You need all of these to have a functional game due to the main board needing power from the sound board, so if the sound board isn't hooked up than the game will not work.
Do you need all of these?