Maybe install the firewall plate after you have the column bracket where you want it. I can't remember if there are slots in that lower bracket where it bolts to the column to but if there is, leave those bolts slightly loose until you have it all positioned. There should be a small amount of fore and aft adjustment.
The breakaway biscuits, plastic shear pins in the steering shaft and the mesh section were all designed to allow the column to collapse on itself in case of a front end impact. Leave that stuff alone. Replacing the mesh section with a solid piece is not a good idea. By doing that you're effectively turning the column into a spear.
