The QA1's are 2.5". You could take a chunk of 2.5" exhaust pipe and see if it will fit through the stock control arm.
But, the upper shock mount is weak, and a 7.5" coilover only has about 3" of travel total. That means only 1.5" of up travel, you will hit the stops constantly.
A bit of stiffening on the upper shock mount and an air shock would probably get you what you want.
I'll help a bit, the stock shock for a mazda is 9.59" compressed, and 15.2" full extend. Look through the mounting length list in this pdf. " and find a shock that is close.
I have the QA1's on my maz, but have not driven the setup.