General fresh air fan box removal

[EJP914]

I am replacing my rusted heater control valve. I have lowered the bottom of the fresh air fan box and want to remove it. Center stack console has been removed already. The heater core is out too.
There are 3 wires coming out of the box for the fan. I have located the blue/black one and the red one. The black one I assume is ground. Where do I disconnect it?
Also, I have read removing this box is a challenge. Once everything has been disconnected and moved out of the way, does it come out the passengers side?
Thanks in advance for the help.
Ed

 

[EJP914]

I found the ground wire for the fresh air fan. It is attached to one of the studs that hold the upper part of the fan box. It is a closed loop connector. Had to loosen all 4 nuts that hold the upper part of the box. The plastic housing does not give enough to remove the wire on only the stud it is attached to. If you were removing the entire fan box, the ground wire would have been obvious, but I had not planned to remove the upper part. The red and blue/black wires for the fan are located above the gas pedal each in their own plastic connection cover.
The lower part of the fan box came out on the passengers (right) side of the car, but it is a struggle. Don't know if any easier going to the left? Too many wires in the way.