I would prefer that the gearbox provide the limits, not the suspension.
No. That's not how it's supposed to work. The gear box is not designed to provide the steering limits. There are bump stops on the steering that provide the proper limits. At least on our first gens. That's exactly why I pointed it out the first time. To get rid of the misconception that the box was the limit. Our boxes are designed to never go to their limit of travel.
And if you really don't believe me, go out and turn your steering all the way and look at what stops it.