I remember printing all the HiSpec drawing and making lots of sketches.
You maybe interested in looking at page 8 of this thread started by my son Michael.Litton Corse build with 2.0l Lancia 8v TC

I have HiSpec front and rear 4 pot calipers with 300mm vented rotors and custom bells on my Litton using 15" wheels. They really work. I used a 5/8" front master cylinder and a 13/16" rear master cylinder. As Tim mentioned earlier in the thread, having the balance bar parallel to the axle line when braking results in great brake pedal feel.
I used HiSpec offset caliper mounts to attain good caliper alignment.
The HiSpec sales guy was very helpful on the phone but email is not the best way to deal with them.....