There are other threads about teensy, but wait some time as system is not ready yet.
I did this year seeding with 0 m antenna hight, and imu GPS fusion at around 50 percent.
On the steer ready cnh t6 175 I know (running AOG ver 4.3) the WAS could not be set completely at zero when driving straight, so we ended up with + 10 cm sideshift of the antenna. No sideshift of machine . This way pass to pass of seeder are perfect, but on screen you see overlap one way and gap the other. Lightbar show konstantly around 10 cm fault in red, instead of around 0 fault like my properly WAS zeroed hurlimann, with hydraulic autosteer.
Also be aware of sidedrag from a seeder in the 3 point hitch. This would look like a incorrect set WAS