Ahh, I see.
MTO w/ PRET Custom as quoted above actually refers to "Pret customization" by Saint Crispin's, where you can add or subtract width on a standard last. An example would be, I had 2 pairs made on UK7F, and later on figured out that they were too narrow. I recently sent my shoes back to Romania where their factory is, and requested it to be re-lasted on UK7.5F, with 3mm added to the toe adjustments. What they do is glue on some wood onto a standard last, and shave it off to millimeter precision as an adjustment to a standard last. I was quoted 60 euroes for adjusting the last, and 25 euro each for polishing and relasting my shoes.