Sight hood just slides on to the front ramp, slots already provided.
Rear sight:
Open Iron barrel sights tap in from right to left in the dovetail already there, brass punch and a little care with the hammer. [ BTW Numrich sells a "folding rear leaf" made by Marlin that is a dandy idea if you are going to add a receiver or tang sight #407610].
Receiver sight: if the left side of you receiver is already drilled and tapped, as many were/are, simple process of removing the plug screws and inserting the screws that come with the sight.... probably going to be a Lyman or Williams for current manufacture.
Tang sight: If your tang has the front screw drilled and tapped, as many were/are, just a matter of ordering the correct sight from Lyman or Marbles and using the supplied replacement rear tang screw and front base screw.
I happen to prefer the Marbles in this application as it is rock solid AND windage adjustable.
Hope this helps
Mike J