Looks like good work, and definitely creative solution. I just have to ask what the problem was in the first place? I've never heard anyone complain about a Mosin safety being difficult to use, probably because no one uses them. I've read about the safety, but I've never met anyone who has actually used it.
Personally, with my Mosins, if they're loaded, I'm about to shoot them. If I'm not about to fire, it's unloaded with the action open.
Same here. You can easily lock the bolt well before you could take the safety off on the Nagant, even with this ghetto mod. The only firearms I use the safety with are semiauto rifles and pistols. Otherwise, leave the bolt handle up or in the case of pump action shotguns, leave the forearm slightly unlocked.