Definitely tie off the wheel. I found that out the hard way. If it gets spun past 2-turns in either direction it will break the coil inside the column. This "coil" is basically a coiled ribbon-wire underneath the airbag. It feeds 12v power to the Airbag and the Horn. If you've broke this wire, its easy to diagnose...you'll have no horn! The bad news?...you have to replace the entire smart-stick assembly (turn sigs, cruse, wipers, etc). The good news?...its cheap and fairly easy to do. Still you can avoid the whole thing by taking the time to tie off your wheel.
Hunner...there is indeed a special tool to lock the column, and it gets inserted into a threaded hole in the plastic shroud on the bottom of the column (just below the steering wheel). There are some screw-holes under there, and if you look close...there's one hole without a screw. Thats your baby. Or a piece of rope tied to the brake pedal works good too.
Also true...if the wheel gets spun, you can loose the index for the VSS. At the base of the column there is a small sensor mounted to the steering shaft. It reads the shaft position, and tells the computer what angle your front wheels are at. Its critical that it remains "centered" or you'll get the KISS concert dashboard warnings. What is NOT true is that you'll have to take it to the dealer to reset it. It CANNOT be re-set via the OBD port. Instead it must removed and reset by hand which involves pulling the steering column. The instructions say it must be replaced with a new one but, that is NOT true either. They just tell you this because it takes some time fiddling with it to get it back to "zero"...and its faster for the monkey in the service department to simply open up a box and install a new one.
This sensor costs $90 and it comes out of the box with a lock-pin on it (monkey proof), and the idea is that you install it with everything properly centered, then you pull the pin to allow it to read. The sensor is basically a teeny-tiny ABS sensor and reluctor ring, (hall effect) inside a sealed plastic housing. I took mine off and inspected it closely. There is a small hole in it, where the lock pin used to be. If you spin the sensor around long enough...you will eventually find the sweet spot where a paper clip will slide completely into the small hole. This indicates that you have found the "center" position, and it can then be re-installed on the column, and then re-installed into the truck.
Unfortunately my wheel got spun during the SAS project, and I was forced to become a self-taught expert on H3 steering columns. There is a lot more going on with the H3 steering than a traditional vehicle, and I highly recommend tying it off. It will save you tons of time and money.