Let�s not lose sight of the principle objective here, which is I guess, to get the O2 sensor out as quickly, easily and cheaply as possible?

While you�re sitting around waiting for your LH drill bits to arrive, why not just cut/grind/file/drill (delete as appropriate) off the heads of the offending bolts, remove the cover and unscrew the sensor. Refit the sensor to your Metal Mule header and off you go!

You can then tackle the stuck remnants of the bolts at your leisure while still being able to ride your bike.

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