I've seen advertisements for a conversion for the Ruger Mk I and Mk II auto pistols that makes taking the bolt out a breeze. Seems like it replaces the existing linkage and adds a socket head screw behind the rear sight for takedown. What is this called, do they work, and where can I get a couple of them??

I hate to be difficult, but why not save the $50 and learn how to take your Ruger apart and reassemble it correctly? It's not that hard. Ruger will send you an owner's manual for free or most any Ruger owner will show you how. There's not a gunsmith around who has not had a customer bring him a bunch of Ruger parts and have him put it back together - after all, it is not something that must be done daily.....

Well hello over in Farmington. I'm in Chinle. I really don't have much of a problem taking them down myself (I have a I and a II) however we have a local guy who just has a terrible time on his Mk I and wants to install one on his. I did some light gunsmithing work for him and he offered to repay me with one of the takedown devices -- thus one for him and a free one for me! I personally rarely find a great need to take them down that far anyway. Most .22 rifles and pistols can go a lifetime without cleaning.