Dynaco VTA ST70 Docking station?

I built a docking station as I have 4 ST70's (I know it's 3 too many) but how come noone builds/sells docking stations? I flip the switch's up or down to see the bias for all 4 tubes. no more playing with meters.
It sits flush .. I just slid it back to show connections - all just plug in.

I was thinking of doing something similar, including a front-mounted power switch.  How do you make the bias meter connections?  Can't make it out from the pics.

octal tube base ... also I connected a "ground" to one of the pins on the octal tags in the ST70 for the neg. side of the meter.