A delivery system for a stent to a bifurcated region includes an elongated shaft with first and second branches extending from the elongated shaft. First and second branches have first and second balloons mounted thereon, respectively. A first guidewire extends the entire length of the delivery system and into the first branch for an “over-the-wire” configuration. A second guidewire extends into the second branch, but enters the elongated shaft near a distal end thereof for a “rapid-exchange” configuration. A guideway is formed in the elongated shaft and extends into the first guidewire lumen. The guideway may be forced open by a guide member slidably coupled to the elongated shaft, thereby adjusting the effective over-the-wire length of the first guidewire.