A simple spring scale, attached to the tail of the airplane, is typically what you'd see used to measure thrust.

Be careful in your assumptions about the importance of thrust. Your plane could have a 4:1 thrust to weight ratio, and still not fly. More likely, you'll prop your plane for a 1:1 thrust to weight ratio and discover that it's a slow dog in the air; it simply won't go as fast as you want it to.