I've done this on my Colt Python. Just unscrew and lift the blade, but beware of the spring, don't let it fly. I shelled out $90 for a white outline Colt sight, so can't vouch for the Riger sight. I know that sight too, had it replaced on a GP100. I am too afraid of Mr Python to muck with it, and the OEM Colt sight is an easy resell like any Python part. Be careful so you can resell the Ruger sight if it does not work out. Good luck on your project.