Sinister Performance 
Well I just got bit by this over the weekend. Fixed a few things on the car and at the same time installed my new wideband in my catless DP.
Having seen this thread in the past, I left the rear o2 in when I installed the pipe months ago and it was fine. So now I replace the rear o2 with the WB, but leave the rear o2 hooked up and tucked up over the heat shield.
Start doing my maf tuning and seeing my LTFT going to +16.4 and I'm thinking!
Replace the WB with the rear o2 and it's happy again.
So either I need to add an extra bung for the WB and let the stock one be, or figure something out in the programming.
I have the right stock .bin for my car from Bill's dropbox. I opened it up with Tinytuner and disabled the diagnostic, but I can't do anything with it in HPT because the VIN/serial isn't licensed. I changed the VIN in Tinytuner, but it won't change the "serial number".
