JBH, I've only shot the Mosin Nagant rifle a small bit but feel that aftermarket front sights would be very beneficial. I found the military front sight to be very difficult to see, especially in low light conditions because it is so slim and pointed. The rear sight is actually quite good and should work just fine. For accuracy, I prefer the block shaped front sight with a flat top and straight sides. For me, it is then easier to align the top of the front sight with the rear aperature and to see equal space on either side of the front sight when viewing through the rear aperature. You sight manufacturer should specify what is required but most aftermarket sights I've seen fit the front dove tail and can be installed by the owner. As a matter of fact, the MN sight adjustment method is to screw the front sight up and down for vertical adjustment and use a drift punch to slide the whole sight left or right in the dovetail. Instructions received with your sight should describe this process. The Smith-Sight looks like a good one to me although I have not used it. Normally, I prefer a thick solid black front sight but have found the fiber optic sights to be helpful on low light shots, especially when shooting at fast running targets. They make sight acquisition faster.