Hello all been out for a while...

So I made a pretty dumb mistake that was easily avoidable. Yesterday I was installing my new Skid Row Engine Transmission skid plate and I was reqired to drill two holes in the transmission support crossbar. On the driver side, when the drill went through, it severed a couple wires on the connector for the "Post Converter O2 Sensor" that I was not aware was attached right above where I was drilling. Should have checked, lesson learned. I now have a Check Engine Light, which the cause seems pretty obvious.

This would be a simple fix, however, I severed the wires that are permanently attached to the vehicle side of the connectors, not the easily replaceable O2 Sensor part. Crap.

I noticed that the wires go up over the transmission and join a larger bundle of wires. I looked through my "Haynes" manual but I can't find anything for the specified O2 Sensor in thier wiring diagrams even after super careful searching... maybe I missed it. The diagrams don't seem to cover everything. Do those wires snake all the way up into the engine compartment, or is there another connector that I can seperate and just replace it easily?

If you have a "Haynes" manual you can see what I'm talking about on page 6-9, Upper Left Corner where the caption reads, "10.3 3.7L V6 engines are equipped with four oxygen sensors - two sensors for each cylinder bank (right side shown) a) Pre-converter oxygen sensor b) Post-converter oxygen sensor" Haynes also states that the Post-converter O2 sensor does not have any effect on the PCM control of the air/fuel ratio, rather that it is used by the PCM to monitor catalytic converter efficency.
Len Taylor, Tim Imhoff, and John H Haynes. Jeep Liberty Automotive Repair Manual. Newbury Park: Haynes North America, Inc. 2009. Print.

I unfortunately do not have a lot of time to spend on this and it is my Daily Driver. How easy would that be to replace? How much do you guys guess a shop or dealership would charge to put it back together like it never happened?

It should be a faily straight forward repair. Unclip the connector from the vehicle and pull it down to give yourself some room. Peel back the insulation in the affected area to get to the damaged wires. For the repair I'd use some heat shrink crimp connectors. Just strip back the insulation on the broken wires, insert them into the connectors, crimp, and use a heat gun or a lighter or something to shrink the covering until the glue comes out both ends. Wrap it up in electrical tape and you're good to go.

_________________
2006 Sport 4X4, Deep Beryl Green, NSG370, NV241J, Lifted with OME 927/948 and Bilstein, JBA 4.5 UCA's, Custom 3" Rear Y-Link Extension and Swaybar Relocation, 265/75-16 Toyo Open Country AT2 tires, Black Plastidipped bumpers, flares, and doors, Pioneer speakers, Alpine head unit, 1200w Phoenix Gold Amp, 12" Dayton Reference sub.

Sorry... going in and out of internet range... but permanently back in now...

So yes, using a crimp connector was my first thought, but the wires are severed literally within millimeters of the backside of the connector. There is literally not enough wire to use any sort of connector. Soldering is certainly out of the question, it will melt the current connector. Anyone know if the typical wire connectors on a KJ can be "reused"? As in... can I take the severed wires out of the connector plug and then put them back in or are they "fused" to the connector with some sort of epoxy seal or something?

The pins inside the connector are pushed into place and they lock inside. You can get them out but normally need special tools to remove them without damaging them in the process. Even if you get them out, you would normally crimp on new pins and reinstall instead of reusing the old ones.

_________________
2006 Liberty CRD Limited

Provent @ 43,000 km
SEGR in progress
SAMCO Sport hoses @ 48500 km
Goodyear Wrangler Duratrac LT225/75R16

If you are a hands on guy you can do it. It’s not actually textbook procedure and YES finding new pins is much, much better, but desperate times call for desperate measures. I have successfully done it in several occasions. 
Especially when you have the clip off the vehicle.

You will need a tiny flat screwdriver to push the pins out and a set of pliers to pull the cable on the opposite direction.
It takes some trial and error until you find the right spot where you need to push for the clip's pin to release, but once you have done one you will get the handle of it.

No need to put way too much strength on it. Once you have the right spot with the screwdriver ad a little pull at the cable side with the use of some pliers and it will slowly come out.
No need to worry about breaking the plug either. If the wires are severed too close to the plug to resolder as you mentioned, you have nothing to lose by trying this any way.
Oh! Almost forgot. Between the pin and the plug you will find a soft sealing ring be sure not to leave it out when you solder the pins to the wires… (been there, done that)

_________________
It only takes one man to place a trail..