The entire frame of the pistol is the 75B. The slide and barrel are the conversion. The pistol's safety, hammer, etc. are the 75 B. It really is a neat conversion - remove the slide stop, take off the 9mm slide assembly, zip on the Kadet slide assembly and voila, a .22 pistol. Of course you may have some initial fitting to do. This is a much cheaper way than buying another gun.
I don't know about accuracy - still testing mine.