Basking spot is too HOT- please lower it immediately to 90* or below! Over that is unsafe- even snakes that love to be "warm" can die from heat strokes.
And double-check all your temperatures- cool side would be fine at 78*- it's essential that you make sure your thermometer/or temp. gun is accurate.
Fix his temperatures A.S.A.P.- then worry about checking his stools.
While snakes going into shed cycle typically prefer the cool side (& humid hides, if provided), I think he's just over-heated.