Took a look at the Haynes and Saturn sports car guides and saw that both use the ford steering rack which has the steering shaft angled below horizontal when the rack is mounted flat. The Mazda rack steering shaft is angled above horizontal when mounted flat. When building we failed to realize this and ended up with a steep bend in the rack U-joint. We’ve rotated the rack slightly to reduce the bend in the U-joint to about 30 deg. This should help reduce uneven steering.