66 barracuda gage replacement

I am in the process of making a replacement gage bezel/and rear panel, to install 4 after market 2 inch gages in my 66 B-Cuda dash. 2 inch gages mount right into the plastic outer bezel with a little sanding in the O D of the gage holes. I will be able to use the rear metal gage support/panel with a little moding on the back to fit the wires for the gages thru. I am usung "Equos" 7000 series blk face gages, all electric.
I am going to have to make 2 illuination bulbs for the speedo, and the vac gage, in the back of the modded dash, and 1 indicator for the high beem lights, that is no big deal. I have to make these cause i will not be using the printed circuits, or the round connector, that connects to the circuits. Their are no turn sig indicators, or brake warning lights, on the dash of a 66 B-Cuda.
So this brings me to my question......... Will I loose any functions of elec stuff, when i do not plug in the circuit boards,????. I can not think of any thing else on the dash, that will be effected.
Also...... where is the best place to wire in the new volt meter,???. Can i use the blk, and red amp meter wires on back of the dash,???.
Any comments and ideas are appreciated.
I am doing this to get a set of functional gages on my dash. I already have an "Eqous"gas gage operating properly. I am using a repared plastic bezel, and rear metal piece, so I am not wrecking the stuff in my car. both pieces were cracked and repaired.
Dave