173rdAbn:  I would send the drill and tap sight back to Numrich for a refund if not as advertised.  Check eBay (krag) and gunbroker (krag);  'no drill' Redfield and Pacific sights show up often.  Both require that the cutoff lever be removed.  The Pacific seems to require that the stock be notched to lower the slide to its lowest positions.  I have seen pictures of a Pacific sight re-assembled with the peep underneath the horizontal part of the slide.  This may eliminate the need to remove any wood.  (I think the peep disk had a 'flat' filed on it to clear the bolt).  The Redfield 'no drill' sights cause a roughness in the cartridge feed, since they do not fill the hole occupied by the cut-off shaft.  Later Redfield instructions recommended inserting a cut-off shaft with the lever sawn off.  A piece of plastic, nylon, brass or steel rod, shaped like an original cut-off shaft, should work just as well.  The "non-micrometer" versions of the Pacific and Redfield sights allow easier bolt removal.  The 'lock screw' can be loosened and the slide quickly raised to clear the bolt for removal.  There is a vertical set-screw that allows an easy return to the sighted-in position.  The micrometer versions of both makes require alot of turns of the Vertical Knob to free the slide from the base, for bolt removal.  Chuck