I've never worked on an M-22 or a M-52, but I have closely examined just a few sopisticated custom jobs. the most recent was an M-22 by Stephen Heilmann, I detailed in an Accurate Rifle story (with cover photo below in November 2001. It has custom bottom metal milled from bar stock, but altered original magazines are inserted through the faux floorplate. (The action was shortened and other extensive alterations accomplished. An extraordinary rifle all around!)
All the hinged floorplate, .22 magazine conversions I've seen, did not have the magazine attached to the floorplate. Unless, I am not correctly understanding, I don't know why one would want to attach the magazine to the floorplate?
BTW, Joe, you'd have to be a great friend to have a good enough friend to give that rifle to, I applaud you!
Best,
Steve
