Pedal goes to the floor... And i am stumped

Volume in caliper bores can be an issue also. Some of the newer assemblies have lining of half inch thick or more. Wear those down to nothing and the pedal must travel further. This displacement issue is very common for hydraulic clutch slaves.
Drum brake wheel cylinders make less noticeable difference of course. Worn linings there would add to the total displacement area when those self adjusters fail.