Since you're already getting most of the parts anyway, you may want to think about getting the same parts for a 93-96 mauser since there is a better selection especially with low mount safetys, plus all of the 93-96 mausers have the gas wings on the bolt that not all 91 mauser shrouds including yours have. In 2016 sent a complete 1891 bolt to a gunsmith to have it jeweled, the bolt handle cut off and a new one installed to clear a scope. By 2019 I had lost confidence I'd ever see my bolt again but luckily had another bolt body that was within .0005" of the same headspace so I have been using it along with guts from a 96 mauser. Little fitting of the cocking piece, but that is expected with any 120+ year old parts.