My car is a BN6 formerly with double-leading shoe front drums and a .75" master cyl. I installed the Toyota 4-piston calipers with Centric ceramic pads. I was prepared to install the booster if the pedal pressure was too high. It was actually as good or better than the drum brakes. Therefore I left the booster off. Does that answer your question?
I think I understand: the booster doesn't make your brakes any more powerful; it just helps you put your foot on the pedal. In my case I can do a panic stop easily enough without needing the booster to stomp on the pedal for me.
I'm interjecting this here because I think it may not be necessary to add the extra complexity of the booster into the system if you use the ceramic pads. I'm suggesting adding those first then seeing if you still need the booster. Moss tech support can tell you if they sell ceramic pads for the older, smaller Girling calipers.