Hi oscar
Just caught up with your build thread.
Looks as if you have made a great start on your build.
With reference to the steering support bearing fitted to the bulkhead.
I think you will find details of that in AshG's build albums. ( Should find a link to that via his profile )
The slots in the CP plate that you mention only need to be wide enough to feed the bare section of the hanbrake cable through. ( It makes life a lot easier & no need to cut the cable in that area )
At a guess a 3-5mm wide slot should be plenty, if in doubt, measure the thickness of the bare section of a handbrake cable & use that as a guide.
One thing I would note.
I noticed that you may have made your steering rack support out of cold bent strip steel ?
Just be aware that strip steel can vary in quality.
I have seen this stuff fracture when cold bent .
Being as it is a critical part of the build, personaly I would have a close look at the bends for stress fractures.
Probably me just fussing about nothing though