Zero Turn Mowers

new Husqvarna 4623 zero turn mower deck leveling problems. The Deck was not leveled properly when purchased and I can not get it right for the life of me. The problem seems to be with the two front leveling Nuts. When alligned parrallel to the mower, the right blade is over an inch and a half lower than the left if the adjustment bolts are equally, making it impossible to level. If i Tighten the right nut in an attempt to bring it level with the left side, it is tightened so much so that it pulls away the rod holding the deck to the left adjustement nut. This makes the left adjustment nut useless as it is not pulling or pushing the rod. Now the front tips are equal but the left rear tip is 1/4 ich lower than the front and the front cannot be lowered. HELP!!!