Hi Ashley
The replacement of the steering rack should not pose a problem - less I think than most cars.
The rack is bolted on to the front of the MGB cross member and this is accessible from under the front of the car without removing the radiator, grille or cowling. The ends of the rack will obviously need to be released from the steering arms first (ball joint separator needed). The column (u/j) end is accessible from under the bonnet. You should then be able to slide the rack down and forward and away from its mounting. There may be one or two other brackets under the cowling which you may have to remove but otherwise it should be straightforward. Don't forget to align the front wheels afterwards.
For the support bearing, see my web site www.ngkitcar.co.uk and look at the steering part of the build section.
Good luck
Chris

Hi Chris, thanks very much for the reply. I've contacted Findhorn about the support and they are getting back to me tomorrow...good news.

I'm currently having a good look around your web site and am finding it very useful indeed. It must have taken a considerable amount of time to compile such a detailed resource, and very good of you to make it available.

And your car looks fabulous! a credit to you. Let me know if you ever plan to sell it!!

Thanks again.