Loosening the front sub-frame mounts and dropping the rear mounts will probably give you enough room to lower the rear of the subframe and undo the sway bar brackets and slide the bar out the end.
Mazda 6 Service Manual: Front crossmember removal/installation
The 6speed does not really change your final drive ratio much at all in this car unfortunately. It mostly just adds another gear to shorten your intervals between 1-5.
3000RPM @ 100kph is fairly annoying but I believe Mazdas purpose was to prevent smaller displacement engines from lugging.
I replaced the aftermarket JDM corner tail lens with a new old stock I ordered from a dealer in Latvia. It was collecting water and turning into a fish tank.
That Latvian dealer sent me what has to be the best packed package I have ever received!
I have used the touch-up pen with excellent results. I use A2N "Performance White" and the pen allows you to squeeze the container in order to add a larger bleb or even to be used with the tip pointed up.
The control arms generally last 100,000mi but can be had for pretty cheap and are not hard to replace. Catalytic failure is present in the 03-07 v6 cars due to a misfire of the COP. When left uncorrected it destroys the precat and this can be sucked back into the engine causing massive oil...