Melt butter or margarine in a small saucepan; stir in 3 teaspoons of the cinnamon and curry and garlic powders; heat until bubbly.
Wash chickens inside and out; remove packets of giblets, if any, and set aside to simmer for broth to use in soup or gravy.
Pat chickens dry.
Sprinkle 1/2 teaspoon of the remaining cinnamon and place half of the onion slices inside each chicken.
Skewer neck skin to body; secure body cavity closed and tie legs tightly to tail.
Place chickens on spit; brush with part of the cinnamon butter.
Set spit in position over hot coals; start rotisserie.
Roast 1 hour, brushing several times with more cinnamon butter.
Stir honey into remaining cinnamon butter in pan; brush over chickens.
Roast 15 minutes longer, or until tender and richly glazed.
Remove to a cutting board; take out spit.
Cut chickens into quarters with kitchen scissors.