Thermostat for lamp question

Right now I have a dimmer on my lamp and manually adjust it as needed, but for a more automated process I know it's probably more ideal to have an actual thermostat attached

I'm not TOO stressed about it since the weather here in SoCal doesn't fluctuate TOO much to where I think with some practice and experimenting I could get the hang of where exactly to adjust the lamps depending on what the weather will be for the day, or day vs. night or whatever.... in the summer time, I'll be surprised if I even have to use a lamp at all, or if I do it would be turned down extremely low

BUT, anyway

If I were to decide to hook it to a thermostat instead, where would you put the probe within the terrarium? I know that with my UTH probe, it was important to keep that taped to the UTH itself OUTside of the enclosure, so what about the probe for the heat lamp? Where would be the most ideal spot? I would assume you would keep it somewhere on the warm side since you want to make sure that's the part that wont overheat .... and usually when my warm side temp is in check, my cool side naturally falls into line too at around 80 and I rarely need to intervene there, so it's more my warm side I want to keep controlled