You would adjust the height of the bulb above the table. You should be able to get 4 temp readings - warm side, cool side, directly under the basking lamp and overnight minimum - check the care sheet for what they should be for Russians. I have a large leopard who lives in his own room so can't really advise on your temps for your circumstances. However I would advise you get temp gun (Amazon £7ish) as these are better at spot checking temperatures than fixed thermometers.How would you ensure that the temperature in the basking spot didn't exceed the 30-32 degrees without a thermostat on the mob bulb?
Thanks