I have the #7194 T/C sight, which came with two screws. It is listed as fitting the Hawken, Renegade, Big Boar, White Mtn. Carbine, and Penn. Hunter. The instructions say:
"Hunting Style Tang Peep Sights require the drilling of either one or two additional holes in the tang for mounting. For the White Mountain Carbine and Pennsylvania Hunter models, two additional holes must be drilled and tapped.
Place the sight midway between the front and rear tang screws, then center the sight side to side on the tang. Use a prick punch to mark the front hole only. Use a #29 drill and an 8-32 tap to thread the hole after it has been drilled. Once the front screw has been secured, then mark the rear screw hole; drill and tap.
For other traditional T/C side locks, it will only be necessary to drill and tap the front hole. The back hole uses the existing rear tang screw found in the rifle. Once secured, with the rear tang screw (and aligned side to side on the tang), mark the front screw location with a prick punch - use a #29 drill to drill the hole, and a 8-32 thread tap."
So, as you can see from T/C's own instructions, for the Hawken, Renegade,and Big Boar, you use the existing rear tang screw, and dill and tap for the forward hole.
Larry