Sounds like the wiper motor is getting weak. I would try to replace the motor first.
As far as the conversion goes, its relatively easy. Remove the wiper arms from the car. This will be your single most aggravating part of the process as will be re-installing them.
Once they are removed, take the ball stud at the motor drive arm, knock it out, drill a new hole exactly 12mm center to center above the original hole, knock in the ball stud, re-assemble back into the car.
Take a wiper arm and straighten the end, re-paint. Install a 24" wiper blade. You can index the arm straight up or off to the passenger side, or even the drivers side if you want.
But as far as it reducing drag, thats not going to happen really. Now you have a full 24" blade that sweeps all the way across the windshield and back. So don't do the modification if you think its going to fix your problem.
You most likely need a new wiper motor first.
(there are a lot of little details I left out above, but thats the basics of how you perform the mono-wiper. Its not that hard.)