I'm probably wrong, but I suspect you want the blade centered on the wheels, then adjust the ball bearing to just miss the back of the blade. So when you start pushing the
wood into the blade it pushes back slightly and contacts the SIDE of the ball bearing. Then the two black guide blocks are adjusted to almost touch each side of the blade BEHIND the teeth. I've heard of people wrapping the blade with a dollar bill and sliding the blocks tight against the bill. Once the bill is removed, the gap is about correct.
I hope that all makes sense.....