PMA5000EX without an external dimmer question

[BJohnson]

Question for those of you with PS Engineering audio panels. If I don't want to use an external dimmer, the instructions say to connect pin 6 or 7 (depending on the system voltage) to either pin 8 or 9 on the J2 connector. This will set the back light to a constant level. But the LED in the buttons will dim with the photocell. I cannot find anywhere that states whether pin 6 or pin 7 is used for the 14V system. Which one is it? My guess is pin 6 but I cannot find a discrete callout anywhere. Also, There is no mention of connecting a ground to pin 5. Is this correct, no ground to pin 5 for the constant backlight option?

Finally, is the constant backlight setting too bright at night that a dimmer would be recommended?