Suggestions which brake setup

If you going a bias box that will need to locked once the balance is set, locked as in split pinned so it can't be adjusted or move while driving. That's the dumb law here in SA. As for vac booster there's a remote booster that hotrods use called a VH44 , old valiants and the escort twin cam had them as standard. Mount it above the light cover under the wing or the front corner in the engine bay. They aren't very big and if you get the ratio right with mc etc you almost don't need one, it'll be there to satisfy the establishment only . Oh, by certain laws you only need the fronts boosted not all brakes.