I measure the oven temperature through the smoke hole like anyone else and I don't plan on changing that.
However, if I were planning on installing an electronic thermometer I would access from the back. With the back off you can take out the insulation and drill directly through the oven wall. I would also mount the probe off the oven wall, with a straighten pipe clamp or other such device (see my thermometer test post).
Another short coming about mounting it permanently is if something happens to the probe, then you would have to go through the whole process again. It looks like the newer Taylor's are wrapped in silicon rubber keep out the liquid and keep it working. Fixing the stainless wrapped probes with oil has also be describe elsewhere.
You still have the issue of heat distribution within even the oven and the natural temperature swings of the thermostat, probably plus or minus 20 degrees from the set point at at the best. The CS thermostat is a quality unit which I doubt you will find on the knock off smokers. If you really want to control the temperature of the oven then replace the analog temperature control of the smokette with a digital unit. But that will cost you a real money.
I suppose it is really a control issue. Q is supposed to be long and slow and with CS you don't have to play with the unit. If you want to play with the cooking why not get a back up stick burner or a Kamado. (Just kidding)