Help me stop!

x2 to the above. What is your MC diameter?

You should be able to use my setup information with compared with yours to get relative ratios;

My setup
Manual disc/drum

15/16 aluminum MC
73-76 abody 10" discs and slider calipers
15/16ths wheel cylinders 11x2.5" drums

I added a $40 willwood proportioning valve to dial out the rear brake bias. I could have also sourced smaller wheel cylinders and may eventually anyways.

it stops well with a very firm pedal. I can lock it up at autox with even with sticky hot tires. I will eventually use a higher friction pad rather than the $10 parts store ones that have been on it since I bought the car and adjust the prop valve back some.