impulse
+1y
I dunno im 6'2" I fit in my reg cab pretty good but its stock floored so loss of head room isn't an issue... but your not losing to much head room with the traditional in the mazda (someone correct me if im wrong) so you might be ok, im also chopping my roof a few inches eventually so i'll be worrying about head room a bit at that time, but I should still be ok, and i'll lower my seats down too.
i think the question you need to ask yourself is are you capable of building a frame to stock floor it?? do you have the right tools? do you know what it involves? are you confident in your welding?
Building a frame is a lot more involved than a tradional body drop.