Ultimate Offroad Mazda - Fuel Tank Mounted!

[@98eck]

Stack on driver side. It's away from tank, probably less exhaust fabrication needed, and if you do turn to look out passenger rear it won't block your view.

[@JesusJoseTaco]

I'd say put the stack on the driver's side, so you can still get full use of the back window and maximum visibility.

[@Jay351]

Stack on drivers side.