What is the best way to get an overdrive auto in a 67 Barracuda?

Good luck on being able to shift a gear vendors to split gears with any efficiency. I drove Mr Angry's Black '68 Charger with a 727 and a gear vendors. The thing was ok to shift into overdrive once in 3rd, but my hat is off to anyone who could effectively split 1, 2 & 3 on a drag strip or even in a street race. There's no way the average guy could master that to make it worth doing in a race. There may be guys out there, but it is very distracting with a throttle wide open.
I'm going to have to agree with this, there is not enough time to split 1st and 2nd in my car, usually paddling the throttle to regain traction, 2nd to third not much time to make it worth splitting either, I was just mainly looking for an OD, that GM auto looks pretty bulky though, what mods do you have to make to the torsion bar crossmember?