You need a vertical spindle mill and the expertise to use it. You also need to fabricate a higher front sight. Brownells sells the adjustable rear sight.
Actually, it is easy to install...especially if it has the top screw on the side of the frame (as on 5-screw guns) or on like the "new classics." I guess just installing a screw on the side of the frame like an older gun would be the easiest, and then if you want to remove the sight, you can just put in the plug screw and your gun looks normal again.
I have a wonder sight on my 1917. It is the easiest way to install a sight. A .32 with a frame mounted sight looks so cool, especially the 4" with a big tall front sight. Larry
Unless you can do the work yourself and have the right equipment, it will probably be cheaper to just sell the gun you have and find something similar with adjustable sights.