Best place to have new pre cat O2 sensor fitted

[warmanguitars]

We have recently acquired a 2002 TF Stepspeed with 40k on the clock. Periodically, and under no given set of circumstances, the engine light comes on although there is no degradation in performance at all. Upon plugging in our own OBD2 reader it usually returns a P0170 Fuel Trim Bank 1 reading. I am therefore guessing that its the pre cat O2 sensor having an intermittent fault. Whilst I am a little bit mechanically aware its not a job I fancy tackling myself and wondered if anyone had any recommendations as to the best place to get the thing replaced. We live in Market Harborough.

[talkingcars]

That is the same code I get with the decat I have on my ZS, personally I'd live with it.