I guess it will be trial and error, good thing Midway had a good return policy!   This is a pic of the tap holes on the Krag I just bought off of Gunbroker.  The price was right and it sounded like the rifle had been massaged a bit by a good gunsmith.  I don't have it in hand yet though, so we shall see.  Those holes look a but skewed, but I figure if nothing else that S*K mount will fit.

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