Wilwood disc brake swap

BBLM23 said
The AlterKtion uses Mustang II type spindles so it may be a little different, but mine was easy. Make sure the safety wire clears the hub. Get the right length studs before you start. My friend says to cut the rotors... I have to agree, I haven't done it yet but I know they need it.

It came with the studs, they're 1/2 x 20, I think. Why would you have to cut the rotors?

How long did it take you to install that?