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I fitted my .45 Rossi 92 with a Williams 5D-94SE receiver peepsight, meant for the angle-eject Winchester 94.
I had to D/T one 6-48 hole atop the rear of the top of each receiver sidewall to accept it, but since it carries the aperture holder bar behind the sight base ILO atop it, it readily zeroed (within 5 shots) using the issue height Rossi front sight blade.
Mine had the bolt top lawyer safety, which I replaced with a low-profile plug (w/o removing the bolt).
http://i.imgur.com/U7F3Zabl.jpg http://i.imgur.com/z1sR2ALl.jpg
Alternatively, the Williams Foolproof FP-94SE sight mounts the same way, but @ 2X the cost of the 5D, has micrometer w/e adjusters ILO sliding adjusters secure via grubscrews.
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