Finding those old pictures would be quite a project so I just took some of the car in the trailer and sent them to your email. If that doesn't get it let me know and I'll get the car out and get better pics.
The removable crossmember is exactly the same as the original except there are flanges on either side near the control arm mount to make them removable and the tubing is a smaller diameter.
The engine is on the same centerline as the original 390. I'm using a Milodon deep pan which is the same as a stocker where the steering linkage passes. I can stick my fat fingers between the pan and the steering so I would say I have a good 3/4" clearance.
Some pics. Higher res in the email.