If im understanding this, your running 2 UTH's? One is on the Hot side and its 92 and the other is on the cool side and the ambiant temp is 75? Is this what your saying? If so, the UTH on the cool side is much warmer on the Floor than the Ambient temp of 75 so there goes your cool side as its almost the same as your hotside Belly heat...
When we are talking about a ambiant temp its usually done with a RHP or a Ceramic heat bulb or heat lamp. Your snake really doesnt have a cool side unless he is hanging from a branch as the Belly heat is hot on both sides....use one Heat Lamp or Ceramic for ambiant and one UTH for hot basking.
(Unless I read this all wrong which is possible, if so im sorry im tired)