Just loosen the turnbuckle on the left till you get the equipment centered, then tighten the right side. Caution, don't snug them up too tight. You need a bit of movement side to side. Also on some tractors the stabilizer chains will get tighter as the 3 PH is raised. I had a Yanmar that was like that.
Check this out by raising and lowering while watching the stabilizer chains and if they get tighter as the hitch is raised, then do all your adjustment with the hitch raised OR in the position where the longest chain length is required.