Got some extended time to work on the car this weekend and installed a PLX wideband AFR.
I got the bluetooth version that displays the readouts on their smartphone app.
Welded the O2 bung in to my Bursch exhaust (this is after a lot of grinding to clean up my sloppy welds).
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After some high-temp paint to guard from rust, the muffler and O2 sensor is installed.
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A screenshot of the app up and running and ready for tuning.
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It was all very easy to install. I routed the connection from the O2 sensor up through the firewall along side the spedo cable. Installed the PLX head unit behind the center console out of sight. Got power for the head unit from an open 12v spade on the fusebox that is only on when the ignition is in the 'on' position. (I gave up on trying to get to the cigarette lighter for power pretty quickly as there's not enough space in there for my hands.)

Bought this setup to tune the engine after installing a rebuilt MPS that now has my car way out of tune. Hope that futzing with the MPS is as easy as it was to install the PLX.

This is going to be one of my next purchases. Can't wait to see how you like it.

Nice ! Where did you order and what components did you get ? I did look at the PLX Web Page....

The one I linked to in my post is what I purchased. It's the SM-AFR Wideband + Multigauge Link Combo. I bought it directly from PLX when it was on sale for $120 a few weeks ago. (It's now $169). It was cheaper to buy direct from them than anywhere else and it comes with most everything you need and some stuff you don't need. The only thing that didn't come with the kit that I had to furnish was a spade connector to attach to the 12v wire that goes to the PLX unit, a 5amp fuse to put between the power source and the head unit, and an O2 bung to weld in to the exhaust for the sensor. I found one on amazon for $3 that was nicer and cheaper than the one that PLX offers. I found one that had a slight curve to the base that matched the curve in the exhaust pipe making it easier to weld.

PLX gives you more than enough cabling to go from the o2 sensor at the back of the car all the way to the dashboard. Also plenty of wire length for power. The head unit for the Bluetooth kit is the same head unit sold with the gauge kit so if you want to add a gauge later you can. I wanted to keep the period look to the car which is why i opted for the Bluetooth version without the gauge. (plus it's cheaper)

I used the same on my 2.0 and the results were great. Very easy unit to use.

Nice !! I've been thinking about one and this one is looking pretty good.

Very cool. No gauge necessary...just maybe a mount on the ashtray.