Well,,, this ain't right. Bank 2 sensor 2... Downstream.
I am changing the sensor from the top. Trying.

Rather than wrestling around with the wires and such with a O2 sensor socket, I decided to just snip the wires, break the end cap off of the sensor and drop a 22mm 1/2 inch drive standard socket socket on it. Ran out of light today so I will go back at it on Sunday.

Removed the intake and TB in one piece (amazingly I can do that in 30min now), and the heater pump (no fun). It's not bad from there BUT I think I may still have to remove the LH trans cooler line from the transmission and it's bracket at the bell housing to wiggle it out of the way a bit for better access with a breaker bar, to free the O2 sensor. Don't want to deal with a rounded off O2 sensor situation.

This was 110% my fault I'm sure. Looks like heat damage from the CAT. Poor care in running wires after the engine swap... I'm paying for it now.

 

Yes, an issue, good job.

Keep in mind that this does not seem to explain the upstream change of connectors changing the side of the problem. You might want to look at the upstream left wire and connector too.

 

Understood... I have the upstream sensor too and have been debating whether to return it and git my 130bucks back or to just swap it, as well... I do need the money. We'll see.

By the way, that sensor removal wrench/tool (linked above) DOES NOT work. For one, it is not 22mm as described. It's bigger. I would guess 7/8ths or something. Then, the handle is wicked short. Nice angle in the handle but a bar of some sort would most likely be needed for added leverage. The handle is a big larger in length and shaft diameter as a 3/8th drive socket...

 

Thank you guys for all your guidance!

Well, the good news is that (without much driving) the fuel trims seem to have leveled and are leveling out. I did go ahead and change the upstream on the LH as well. Seems to have had some positive effect on the RH trims as well...

Super thankful to the last guy who worked in her. Wasn't much of a tough twist to break free the old sensors. They were carbon messy.

Problem is, I am still struggling with the DTC setting themselves as ready for inspection. In all this, plus the time in weekends for the engine swap, the registration has expired and a renewal is not possible without a current inspection. Dhaaaarrrr! All but catalysts, O2s and "components" are ready. The 3 mentioned are holding out, lol. Guess I have to do some night driving as day driving is usually bumper to bumper.

One of the shots below is the work area with the TB, heater pump and needed bits removed, including the loosening of the trans cooler line at the side of the trans. All accessable from up top.

Used a tool similar to this one.

This with a breaker bar.