One of the big things I don't understand is the different valves/blocks. If I have 12.19" 4 piston brakes in front and 11" 4 pistons out back, do I need any kinds of valves or could I run straight lines since they're all disc and the front rotors are bigger? How exactly does this work?
Generally when I do a 4 wheel disc set up, no proportioning valve, no distribution block, the rear line directly off the master, the fronts directly off the master with a tee downline to break left/right front, I generally bend/form my own stainless hard lines, you may need an adjustable proportioning valve for the rears if you haven't sized your F/R caliper piston size to create an ideal 60/40 F/R brake bias, worse case scenario I would allow before adding an adjustable PV is a 70/30 F/R bias
FYI, I temporarily install 4 hydraulic gauges one at each line/caliper end when I create a system so that I know exactly what pressure/bias I'm creating, I strongly recommend installing gauges temporarily as you design your system, I use gauges rated to 2000 psi, needed esp on a power assisted system, you can tee the gauges and the bleeder screw directly into the bleeder ports on the calipers, bleed and test the system in one shot...
Mike
