Page 142 in the green Haynes manual shows how you'll need to set up your system. Although it calls the individual systems "primary" and "secondary," I think they are both applied equally. The systems name, "dual diagonal," describes its function rather well.

As for existing part compatibility, I know master cylinder bore diameter influences line pressure. The rear cylinders are designed for their respective pressures. How this all fits together I haven't the slightest idea, but someting to think about. You could always replace the rear proportioning valve(s) with modern adjustable units. That way if you get it wrong the first time you can just twist the knob until you have it how you want it.

Oh yes, don't forget about a booster. Easiest would be a 140 unit, but I don't know what you already have.
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Justin 66 122E, 71 145S
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