You have a great foundation for your project, I love the '17 for many reasons. Now, bolt sleeve threads... yes, Win 70 pre-64 shroud assy will screw into 1917 bolt....what I don't know is stuff like striker length and compatability, model 70 striker and cocking piece fitment is radically different from Mauser style of the '17...but I'd remark that the '17 safety as issued is one of the best IMO. You are ' trying to improve something that IMO doesn't need improving. Just one old guy's opinion. The argument for the half safe position of the Win 70 style for reasons of unloading the magazine box fall a little flat when you can dump the mag safely on any CRF rifle without closing the bolt into battery...by just stroking the bolt fore and aft. Perfectly safe and quite fast. In the interests of harmonious relationships betwixt cousins...I am not a gunsmith, I work on a lot of guns, I am best described as a blacksmith with a machine shop.
