kevin, My GRF 20ga. trade gun lacks a rear sight, and truthfully I don't miss it. However, I did cobble one up from a pc. of ancient O scale brass rail (as in model railroading). I used generic Crazy Glue to affix it to the bbl., but found I was no more accurate with it attached than without it. Before you alter your bbl. or tang, think about making one and trying it. If you don't like it, you can simply remove it. Btw, another advantage of this [method] is you can experiment with how far forward the sight needs to be for you to get a clear/focused sight picture.