Well . . . not really. You want to measure smoker temp at the grate level, not several inches above the grate and the meat. Plus when you put the cold meat on if the thermo is above it, it will read much lower than the temp under the grate which is what you're trying to control.
The side mounted thermo works fine. Just compare it to a digi probe at the center a few times so you know what the difference is and do the math like Rick said. It's really no big deal. I try to keep my side thermo between 180° and 200°. On my drum that's a center grate range of 230° to 250°.
You can also do the deep fry thermo through the bolt. I had mine set up that way for a while.http://www.smokingmeatforums.com/for...ad.php?t=80519