TH2: binX size = binY size

Yes but I have several plots on the same canvas, and especially a palette that makes myplot not square even if my canvas is. Maybe by playing on TFrame ?
Attached is an example, I have c1.old.gif and I would like c1.new.gif (with the 2 left hand-side plots centered on their respective pads if possible).
Cheers, Zesp