All kinds of Dam error codes!

[Revolver Ocelot]

Dam i got a check engine (95 SE) light today and got six error codes. They were:
105(EGR and canister control valve solenoid)
12 (MAF)
33 (Front O2 Sensor)
34 (Knock sensor)
41 (Intake air temperature sensor)
65 (Misfire #4 cylinder)

I searched and found that the knock sensor cant set the check engine light off by itself. I also just changed the plugs and wires so that should take care of the misfire.
1st.) I just replaced my water pump too and when i did i unplugged the MAF and Intake air temperature sensor from the airbox. Could this have caused the Error code?
2nd.) The front O2 sensor is the one plugged into the exhaust manifold right? Should i just replace it?
3rd.) I found a few threads about the EGR but none of them ever answered the question. What should i do about this?
Well thanks for reading my long ass post, any help would be appreciated.
Shawn.

[sr240mike]

Reset the ecu and check for codes again. EGR can be replaced or blocked off. Do you know how to do the o2 sensor diagnostic with the ecu/check light? PM me if you need some help.

[Revolver Ocelot]

Thanks Pm sent!