At both the trigger over travel stop location, and the original trigger spring location.
The mechanical advantage of the trigger makes for a very sensitive trigger pull weight.
Some machine work required
Drill and tap for the 10-32 thread requirement at the Over travel position, and an adapter sleeve in the tension spring location. (Needed for the AR series trigger, drill and tap for the QB series)
A smear of Crane Cams Assembly Lube (moly) at the contact points goes a long way to making for a creep free feeling at let off.
I prefer a generous first stage and associated sear engagement, with the release only a wish beyond the felt second stage resistance.