Well following soem helpful advice from British Trident I've got myself a Mk.1 Fiesta master cylinder to try and improve my rubbish/non existent braking.
The MC is a 50/50 split I believe so I was thinking I'll need some kind of limiter to the back brakes. I know you can get the standard equipment like the one on the Sierra but I don't know what these are rated at does anyone know a suitable one?
I thought of one of these in line adjustable knob things as well. My problem is, how would i lock it for SVA? Would lock wire to two sides be enough?

Use adjustable knob thingy to set brakes then take knob bit off,
You wont want to change bias once its set unless you are a top notch racing driver or change brakes in the future

Ah, good idea. Didn't think of that. Knobs are not generally at the fron t of my thoughts Cheers.
Oh, I'm not even a bottom notch racing driver. Though I'm not bad at Forza

You shouldn't need a bias valve unless you have fitted over sized rear brakes.

If you feel you need one the valve from a FWD Ford such as Mondeo or some Fiestas is the easiest option.

I would warn against Wilwood stuff most it was designed for brake systems with which operate at much higher working pressure than is generated in a Seven style car as a result the valve will have no effect at all.