[Howardk]

You'll have to swap out your old mainspring and the top and bottom caps. Simple to do. The easiest way is to put the old mainspring housing in a vise, push down on the plunger and remove the pin. Keep pressure on the mainspring and lift it out. Reverse the order for the new mainspring housing.

 

[col132]

or, you could buy the whole assembly and have a spare, or an extra set of parts. No problem changing them out, I just like to change them around more than what a normal human being should. Seems like I never, ever, have enough internal parts for mainspring housings.