Rubbermaid heating.

[wizbit13]

Howdy all. I have just received my new infrared temp sensor, and checked the floor temp in my ball pythons rubbermaid. It is a little colder than what I had expected. 86 degrees. I have the rubbermaid stood about half inch over the heat mat. Should I just drop the rubbermaid down a little to get it closer to the heat or should I put the rubbermaid right on top of the heat mat, and just turn the mat down a little to give me the right temps?? Basically what i'm asking is should I leave a slight gap between the rubbermaid and the heatmat or sit it right on top and adjust the heat accordingly??

Cheers

Adam