AFR misleading? Plugs tell a better story?

Looks like the 1” listed in the link posted above is actually 1-1/32”, so I guess I’ll give the 15/16 or 24mm (same size) a try. Also will need to make an adapter plate and push rod for manual MC.
Here's the Wilwood master cylinder I have. 15/16" diameter piston bore. Quick Performance is the vendor.
950-261-13626-bk.jpg
The salesman I've been working with said that bore size master would work well with the slave cylinders in my setup, the calipers are unique in that they are SIX piston calipers on ALL 4 wheels. Anyway he said the combo would provide some good pedal travel, which is desirable to me, and allow for plenty enough force multiplication to lock up all 4 brakes should I press hard enough.
Wilwood 261-13626-BK: Aluminum Tandem Master Cylinder Kit Black E-Coat Finish | JEGS