I am sure everyone is tired of reading my crap. (I am a visual learner).

Some images:

#1 - model 1898 sight (top) contrasted with model 1902. 

#2 - model 1902 slide - (note faint circle around hole, showing margins of 'shoe' insert. On some slides it looks like a football shape). 

#3 - model 1902 sight taken apart - ('shoe' is not removable).

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