Here's a pic of the steering box clearance. I basically set mine back as far as possible during mockup. Of course I had my headers installed, and I put the steering box on, to make sure all my stuff was covered. Having your oil pan on will be mandatory to ensure your golden on fitment. I'm using the Holley pan. It's about 1/4" off the top of the crossmember, and I also have a ton of clearance on the sump of the pan to the crossmember. I researched this a lot. Some people reported that they had to raise the engine, in order to get tie rod to pan clearance. My engine is as low in the car, and as far back in the car as possible with a stock firewall, and I have no problems anywhere.
Now I have to go update my build thread with new pics. I finally got my body on my chassis!