Why do you want to use a road stem, besides the bargain? This is one area I would not cut corners on or fudge. Believe me....I have a nice long ugly scar up the side of my left thigh as testament to what can happen. Jagged metal has a way of ripping open flesh. Another inch and I'd be singing soprano.
Check out Sheldons page
http://www.sheldonbrown.com/handsup.html