http://mechdb.com/index.php/O2_sensor_simulator

i can't find the exact schematic i used but i'm pretty sure its the same thing... next time i have my seat out i'll take some pics and throw it in the how to section

i've done something like this as well as a heater bypass(see connecting heater wires to the upstream 02 sensor) on my car as i've fully removed my rear 02 sensor and got no CELs

i've also got an access port and has my tuner disable a couple additional codes

 

I would suggest doing the defouler trick. The 90 degree adapter pushes it too far away from the stream to get any reading that's why it seems like you're getting a code. The UR TP already has the sensor angled from the stream so the defouler should pull it far out enough. If it doesn't work then at least its only like $5 to try and keep yourself from buying a stock cat from somewhere.

 

Instead of doing the 90 degree bend spacer I would recommend a straight spacer like the one in the following link. I have a straight one similar to this and have never gotten a CEL with my HFC.
http://www.lancershop.com/customer/p...&cat=68&page=1