Here is our enclosure: https://imgur.com/a/d2S0biV
On the hot side I have a reptile radiator on a microclimate dimmer, underneath I have a 25w mat on a microclimate pulse
IR gun temps of my room range between 12 and 15c (with the storm going on at the moment I would guess that's colder than usual)
Cold side of my tank is only reaching 19.5c according to placed in thermometer on the substrate, another thermometer probe is reading 23.6c higher up on the wall on the far cold side. Gun readings showing 15c on individual coconut bark pieces
Hot side ground thermometer reading is 26.5c, whilst gun temps of the top of the resin hide show up to 37c at the top most part, while 22c on the coconut bark substrate just inside the hide.
Cork wall on the hot side 31c at the top, down to 28c at the bottom.

How the heck do I sort these temps? I have some window insulator arriving tomorrow for the front and top glass: https://www.amazon.co.uk/dp/B00NVI3D..._e0SqEbG2FCHFP

I feel like this won't be enough to sort out the crazy fluctuations. I would turn the radiator up but then the top of the hide would get even hotter, while I have no idea if my snake will be smart enough to avoid trying to lay directly on the hide.
Would a good rule of thumb be that if I can hold my hand on it, it won't cause the snake to burn? Or would it get burned at 39c, because it barely feels hot to the touch just rather warm.
Any and all help would be greatly appreciated, as our snake arrives tomorrow (had 2 weeks to sort all of this out but there were way more shipping delays for parts than I had planned including an obliterated resin hide, while his cold side hide still hasn't shown up after being ordered over a week ago)

P.s. ignore the gas struts, 60N was enough for the lid but I completely forgot the radiator was being attached to the ceiling, so now I need stronger ones