Todd,
Your pictures look great. Main reason why you are not having any problems is because you are not using the stock steering box, which is normally right on top of the rail, right where your headers begin their curve downward.
It is possible to relocate the stock steering box more outboard, which is what I'm looking into now. It does move outboard, but only so much before hitting the inner fender. Any more than that would probably require trimming the inner fender for clearance.
I would very much like to modify my truck for rack and pinion steering, and it looks possible, but I would have to make my own modifications. With a welder, the conversion does look fairly simple.
