Thanks for the help kcress. I feel like the theme here is motivation to do things correctly through shame.
Ok, so I went out and bought a level. When I put the level running front to back on the left most side of the stand, the bubble is between the gauge lines, but slightly towards the back. So the back is slightly taller at the left side. At the right side it's the opposite. Although everything is slight. Assuming this is the problem causing the tanks to have a slight wobble, how would you go about re-squaring everything?
Thanks,
FB