The Talley is a QD unit with a finely serrated "knob" that is hand tightened to secure the base. There is no groove to allow the use of a screwdriver. At least that is how mine is. You will need to have your base modified to accept the peep sight.
EdM, just so I'm sure how it works, if I was using these as backup sights for my scope I would have to remove my scope and then mount this sight to the rear base? It isn't mounted along with the scope, correct?
Thanks, Gord