how do i know if i have the new or old style sights? i looked at the originals from brownells but they only specify old and new style, no measurements to go by.

i have an 1894P that i installed an XS scout rail on and i removed the factory front/rear sight assemblies and sold them off. now i am looking to put something back on. ive seen the XS peep sight setup and was wondering if its a straight drop in on the factory tapped holes? any other reccomendations...

can you rccomend a couple?