Jim n Iowa;
I have installed a green Fibre-Optic front bead on my M-71 Winchester which has a tang rear aperture sight (Lyman #2 for 1886). The improvement was so significant, that I immediately did the same on my Marlin 336-.35 Rem. which is equipped with a Lyman #57 rear aperture sight.
With an aperture type sight, the bright fibre-optic bead allows the shooter to really forget about anything else except the target and the front bead. I have used scopes a lot over the years as well, but for shooting under 150 yards, the aperture-fibre-optic combination is IMO unbeatable; trouble free, fog free and tough. The poor light in morning and evening are actually the best times for this type of sight; with the green tubes providing a little more light than the red.
The brand that I chose (HI VIZ) provides 6 fibre-optic sight tubes of varying size that can be easily replaced on the metal dovetail base. It's an easy changeover, and you can go back to your original front sight if you want, but I bet you never will! And just ask the moose and deer in my freezer if they work.