Alan: I have a Williams peep on my Versa-Pack .22. The design of the Versa-Pack barrel requires a very high front sight, so I attached a Williams Shorty 3/8" ramp, and installed a Fire Sight bead. Williams aperture sights don't seem to sit as low as factory notch sights, so you may need a higher front sight on your Sportster. Opening and re-threading the tiny factory front screw hole to 6-48 allows you to experiment with different ramps and beads.
The original WGOS base is pretty high, so I took an old base from a lower Williams factory rear notch sight and used it with the fittings from the WGOS to make a lower aperture sight mounted in the scope-base holes on the barrel. The screw spacing is not correct, but so far the sight stays put very well with only one base screw holding it in place. This arrengement is okay for a .22 LR, but a center-fire rifle should use the correct Williams WGOS base, which mounts in the rear two scope base holes.
I really like the handling of a rifle with iron sights -- a scope adds weight and makes a Handi-Rifle less handy. My aging eyes aren't good enough any more to shoot well with a rear notch, but a peep and a light-gathering front bead solve that problem.
