Hey Steve, here's my advice.

Fit them one at a time to see what they do.

O2 controller first, since it's the easiest.
Go for a spin, find out it's amazing.

Kev mod, and DNA filters next.
Go for a spin, feel the power.

You can cut into the air sensor wire without taking your tank off. Just push the sensor out with the LHS air box cover off.
Make sure you do that join as a permanent fix, would suggest solder and heat shrink.

It's dead easy, but good luck and enjoy.

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Bike: 2013 XT660Z, TKC70 tyres

Mods:
Barkbusters, Scottoiler, DIY Tail Mod, DNA Stage 3, Power Commander V & O2 Eliminator, Exan X-Black Stainless exhaust, Tool tube, Ohlins linear front fork springs, Nitron rear shock, JT front and Supersprox rear sprockets, D.I.D. VX 520 chain, Adventure Spec bashplate, DIY USB Outlet, DIY chain guide, Kev's Throttle mod

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