Hangar Flying

Hello, glad to be here!!! I have bought an used Long ez, It flies quiet well but I have to do some work on it. One of my concerns is a vibration on the winglets and the ailerons, mainly on the right side. First of all I balanced the propeller, Second I did a dynamical balance and now I'm thinking to change the engine mounts. The vibration happens in flights and being on land with full power. I will greatle appreciates any idea. Thanks. Michael