Mods, please move to any appropriate forum.
I finally got it. It involves a combination of various techniques mentioned previously.
-- No steps require work from under the car --
1. Disconnect negative battery cable
2. Remove coil pack
3. Disconnect O2 sensor connector
4. Unscrew two bolts that secure wire harness
5. Place slotted O2 sensor socket on O2 sensor (ie squeeze one hand behind wire harness and under the two metal pipes).
6. Lift wire harness up off the two bolts and slide towards the firewall.
7. With space created by moving wire harness, slide 1" open end wrench in front of wire harness and onto the hex portion on top of the O2 sensor socket.
8. Unscrew O2 sensor with wrench until it can be further loosened with hand.
9. Move wire harness back to original position (to make room for hand). Remove socket from the sensor and loosen and remove the sensor with hand.
10. Screw in new sensor until hand tight. Slide O2 socket over new sensor.
**11. Slide wire harness back towards the firewall.
**12. Tighten socket (sensor) with 1" wrench.
13. Reconnect sensor connector.
14. Reposition and resecure wire harness back to original.
15. Reinstall coil pack and negative battery cable.
** Replacing with a Bosch unit negated me from completing Steps 11 & 12 because it is a taller sensor than the OEM one. So, I was not able to slide the O2 socket over the Bosch sensor to then tighten with the 1" wrench...
Solution to **:
A. Replace with Denzo unit (if that sensor is similar in size to OEM one), and then follow Steps 11 & 12.
B. Use a deep offset 7/8" box wrench. Slide the box end over the new sensor's wire and down the sensor. Tighten.
