How to Get 1991 964 to Pass Emissions

[FuDog]

This is my first post and my very first Porsche experience, I am super excited.

The car just got delivered a week ago via enclosed transport. I got to drive it for one day and had a blast then the next day it started snowing so put it up for winter. I had to put a trip permit on it until it passes emissions. This why I am here, I need to get the car to pass DEQ (emissions in my state). The car has a cat bypass on it.

I have the cat so I can put it back on to pass emissions. I took the car to just see where it was in terms of the co levels and it blew 7.4 co but the state I live in i was told they only allows 1.0 co or below levels.

Also the oxygen sensor is just hanging on the left side. I was told by the previous owner that it was that way for a reason. Of course I can add the cat back. I also was told that the Oxygen sensor won’t do any good if the frequency point on the fuel head is missing for performance reasons. But i dont know how to tell if its there or not.
But if it is there to just plug it back in and at the cat back and should be good.

So this is my question how can I get this car to a pass, what should I do and how to do it?

Now remember I am a totally newbie to Porsche's. So please if you respond be as specific as possible.

Thank you in advance for any insights.

Below are some of the specs.
1991 Porsche 911 Turbo “965” 71K miles now ( 66,800k performance rebuild done)
It has a 3.3 liter Turbo engine that just had a full all out rebuild.
A full street performance valve job, Main Bearings, Oil pressure switch,
Rod bearings, Intermediate shaft bearings, Timing chains, Chain rails set,
Valve guides and stem seals, complete piston ring set, ARP rod bolts and nuts,
ARP 4206 head studs, Piston pin clips, Oil return tube and seals, Main seals, Oil pump seals and lock tabs, Oil cooler seals, Cam key ways and pins, Case O’ rings, Head copper shims, Upper and lower valve cover gaskets, all other gaskets and seals and crush washers.
High Flow TurboS
GHL SS full exhaust with heat and CAT bypass.
IA high air flow intake system
Tail wastgate WG46.8 46mm 1 bar spring.
Rebuilt the Fuel Distributor to boost flow rate.
It also has a C2 light weight Flywheel with a C2 LW stage 1 Clutch, Pressure plate and release bearing.

[AFM744]

I'm not clear on your fuel head mod, was the frequency valve removed? Was the WUR (aka control pressure or warm-up regulator) modified?
First I'd get the O2 working properly. I'd install the cat. I'd then have the CO measurement checked. If it's off then have your warm control pressure checked. (I don't remember right now what it's supposed to be on our car... 2.8b I think)
Once the control pressure is established then adjust your idle CO with the 3mm fuel head adjustment.
I've criminally over-simplified these tasks, but start with getting the OEM emissions controls functioning, then have the CO tested and go from there.

EDIT: FYI our engine for all intents and purposes is a 930 engine and this info is best posted in that forum.