The way I've been told to do a car is to first suction any fluid you can get out of the master cylinder with a turkey baster. Then pump as much fluid as you can through the bleeders with the pedal. Then fill the master cylinder with new fluid and flush through until what's coming out of the bleeders is clean. Refill the master cylinder. If you want to be really careful, let it set overnight so the new fluid absorbs any moisture in the system, then repeat the process.