To add to Rich Montague's answer above, YES I am currently converting ALL my "expensive" 3rd Rail brass steam locomotives AND "expensive" MTH Premier steam locomotives to Kadee couplers! I already have over a dozen converted, including my Lionel Legacy UP FEF-3 and SP GS-4 4-8-4 models. Some are MUCH easier to convert than others, however what also takes a LOT OF TIME is removing that damned diecast mounting extension on the rear truck for the big electro-coupler on MTH models! I have already taken two truck bolster pieces to the vise in the garage and hack sawed off that extension! In most cases, if you do NOT remove that extension on the rear tender truck, it will NOT clear the Kadee coupler box assembly, thus the truck swing will be restriced on curves (my "sharp" curve is 072).