Temporary tub cage setup help

[trailblazer295]

Hi girls and guys

I'm in the process of setting up my BPs old 24x24x12 pvc cage for a childrens python. Unfortunately due to the tiny size of juvies one would be able to fit his nose and part of his head between the spaces in the vents and as well the gap around the door. On a recommendation by my local reptile store I bought a tuperware tub to place inside his future home until he grows enough. Now the cage itself has a UTH on a ranco stat and a pro products rhp on another. I've positioned the tub so the left half is under the rhp to get a thermal gradient. The substrate will be papertowel in the tub and coconut husk when he upgrades. He will have 2 hides and his water dish in the tub. I've drilled 1/4" holes in the side of the tub on all sides spaced about 2" apart for air flow and intend to place a bowl of water out of the tub under the rhp to aid in humidity.

Is there anything else I should do or a better temporary setup without buying equipment I'll only need a short time?
Where should I place the temp sensors?
Where should I put the humidity sensor?

Any other tips?

Thanks for the help
Scott