K-H brake swap done, but doesnt stop!

You don't need to take them apart you can tell right on the car. Have someone apply the brakes while watching the calipers and turning the rotor. If that is not enough, pull one or the other caliper and retract the pistons. I just use scrap wood and a C clamp. These are dual piston? So you'll have to devise necessary adaptations. You should be able to easily retract the piston by using little force on the C clamp

Don't force them too far if you have the master filled up, or else remove some fluid first. Likewise, after retraction, either reinstall or put some wood between the caliper to mimic the rotor, and go apply the brake. Pedal should go down fairly easy to "take up the slack" and re-position the piston.