to determine if the spring would have gone through. measure the hole and rod, compare the clearance to the wire diameter. the details of how to measure using a triangle of printer paper wrapped around the rod can be found in a search
I took a slide that was near failure, the clearance was near wire diameter so the spring could be forced out. I then drilled the guide rod hole so the clearance was 2 wire diameters, thus the spring would fall through. Then inserted the nylon washer that princemoore has and the gun has worked fine, with no signs of wear.
the clearance to the rod is nil, but since the nylon gives when the rod tilts during recoil, it is held exactly in the center and feels much smoother
Something to look out for. KT designed the pistol so that the spring goes solid at the same time the slide hits the frame. by adding a thick washer, the spring will go coil to coil before slide hits the frame and put a kink in the springs.
Again a search will find the details of the measurements and how to look and see if the spring went solid. it is basically look between the grip and the slide and observe whether the slide makes contact when it is pulled back with minimun force
(sorry for the delays in posting, motels internet connection is poor)