URD O2 simulator Question

Hey guys quick question here.

Im diagnosing a shitbox of a truck and need to know if the rear O2 sensor still needs to be in the exhaust stream with the URD 02 simulator plugged into it?
There is currently no O2 sensor bung welded in for the rear 02 sensor so Im wondering if the URD simulator is doing anything with the O2 sensor not being in the exhaust.

Im trying to get a basic idea of the issues this truck is having. Its a 90 pickup with a swapped 97 3.4 in it. However the PO did some complete hack work and Im just trying to narrow down some of its issues.

Thanks and ask if you need any clarification.

 

Other simulators can completely replace the sensors. With the URD sim, the sensors need to be in the exhaust. If it is similar to the 2nd gen?

My question is, does the sim have plugs for the harness and the sensors?

 

Hmm, that is what I was thinking.
Yes this appears to have been a "plug in play" model, that just plugs in between the sensor and harness.

However for some fawking reason wires have been,cut, soldered, cut again, crimped, cut, twisted and taped... etc etc. Freaking nightmare!

If anyone has any other experience let me know, as Ill probably be working on this for a while.