I done just that to a sled about 5 yrs ago. It was a quick fix the night before a big ride.
The steering column broke off just below the handle bar clamp plate. Yes it had the Mt Performance support stud installed. I found a 12" long (long enough to go in past the top support) solid rod that was a nice and tight fit, and grooved it for the seem weld in the column. I drilled a hole about 1 in down from the top of the existing column. The guy wanted it raised up 2". So I put the rod up through the clamp plate and welded it on top and bottom first then stuck the rod in the old shaft. I held it up 2" and welded the rod to the column and plug welded the the hole I had drilled. I did it all in the sled. I removed the airbox and put a welding tarp down over the engine compartment. It has been rode hard and rolled several times. He has replace bars and hoods but the steering column has not broke.