Crosscut Jack,
Miculek does provide a warning regarding his springs (at least for the K,L,N frames) which
says:
"This spring kit is recommended for target and competition shooting. It is not recommended for defensive handguns. If reloading, make sure Federal Primers (which he recommends for his spring kits) are fully seated into primer pocket."
I'm assuming a Mod. 60 is a defensive handgun, so if you install his kit, I'd recommend that you test several types of ammo you plan to carry, be they Winchester, Federal, Remington or the many others available. You'll want those primers to be set off every time--every time.
Danski