You already have a quarter rib, all you need to do is open up the notch to accept a 1 standing and 2 down leaf sight from Brownells or NECG..Sight it in for 100, 200 and 300 yds...once you get it filed in for 100 yds. the other two fall into place real easy.....OR

Use a one standing sight and sight it in 1.5" high at 100 yds. and call it good.