Solder the loose grounding straps to the ground pads on the interface board. It's recommended that the HV led is copper taped to side of the box. If the HV causes noise when the device is operated, you may want to cut off the SHV connector from the tube's leads shorten the leads. The time constants of the shaper can be adjusted with potentiometers on the repeater card. After initial hookup, there should be no need to open the aluminium box in normal practice.
Batteries work nicely.
A ribbon connector to the controller module, pin 1 towards the outside. The current in the tube is essentially zero. 2 LEMO output cables which go to the BNC-2090 box. The Viking chip timing is controlled by a NIM module. With experience, you can estimate the noise by watching the levels bounce around for different triggers on a scope.