I'm about to order a Fastfire 3 for my 870 I've been transforming into my turkey gun. My question is concerning themmounting. I'll have the gun drilled and tapped for a 336 mount so do I need ro order the sight with no mount? Excuse my ignorance on this, just don't want to go through the trouble of ordering the wrong thing. Any other suggestions on mounting will be appreciated if I'm going about this wrong. Thanks for the help.