Hi Bar44, it is not too hard to swap out parts, having them fit properly is another matter all together! But as for your question as to what is, and how to? Just do the following; Make sure the Luger is empty, then field strip it down to the toggle train in hand. On the rear toggle, the pin that holds the coupling link, has an ear bent up on the LH side, and you need to drive it (the pin) out from right to left and it will free up the slider assembly to come off the back when you depress the slider button and slide back.. Reverse the sequence once the correct fitting parts are selected... That's it, not too tough at all... best to you, til....lat'r....GT....
BTW, you needent drive the coupling pin all the way out? Just far enough to let the slider go past... That way you don't have to keep track of the pin and parts so much?... best, GT