Correct Method to Measure Temperature in Growbox (direct light vs shade)

Hi All, just started a new grow with a PC tower growbox I made. I have been reading a lot and have a decent setup with seven 23watt CFLs with lots of exhaust fans (3 x 89mm and 1 x 120mm) towards the top of the box and two intakes at the bottom (they also serve to help circulate air). I read a lot about temperature recommendations but have not come across a good discussion on how to measure the temps. If I place my thermometer on the floor of the grow box, my temps never go higher than about 3-4 degrees above ambient temp (ambient is high 60s to low 70s). If I place the thermometer right under the light, the temperature goes up to low 90s. Now I know that this is partly a result of radiant temperature on the thermometer which does not give an accurate air temperature. Also, if I use a box to prob up my seedlings closer to the light source, and place the thermometer in the shade, the temps are also lower. In summary, I can get wild swings in temperature measurements depending on where (how high) and how (in shade or direct light) I place the thermometer. This leads to two questions: 1) Recommended temps are usually low 70s to low 80s. Does that refer to shade temperature? or measured temperature at the leaves/ buds? (i.e. When we check the weather, and it says 80 deg and sunny, that's shade temp....it may be 100 in the sun). 2) I just started from seed and the plants are about 1/2" tall. I tried to feminize them with banana peel (ethylene) method for whatever that's worth but figure no reason not to try. I know that one of the factors that effect gender outcome is temps. I am trying to figure out whether it is worth lifting the seedling up to the lights where i get temperature measurements of low 90s (and get less stretch and more lumens) or keep them on the ground (where the temps are mid seventees) and increase change of females. They are lifted up right now but I am seriously considering dropping them to the ground because I started with only two seeds and don't want to get assed out with two dude plants. Also, I have a decent amount of CFLs (161 watts crammed in a tiny box), so i probably have enough light for vegging without serious stretch. Once I kick them into flower, I will get them closer to the CFLs. Any thoughts are welcome! I am attaching a pic of the box just in case (its a mid tower with white elastomeric paint). Thanks!