Let me tell you what this guy did to his t-28.
He added 3 inch triange stall strips to each wing root (next to fualage) on the leading edge and now this plane flies like a baby.
You see these on a lot of Beechcraft airplanes to make the center section stall first.
I have done the same thing to a scale Glassaire made by Bryon Originals back in the eighties to tame the tip stalls down.
I have a large scale Stinson Voyager (see my profile) that I am going to cut wing slots in this winter as the real one had them.

Raiseing the airlons up a little on each wing helps also like Ron suggested.
Jim