You could always try alternating the breathing, so breath every 3 strokes that would at least cause your arm to come out the water and go over your head when your trying to breath to that side! IMO Depending on your current "swimming fitness level", you may be able to cut your time down by that much. IE if you not that fit in the water it will easier to acheive greater results, so more possible for you to hit your target!
Ps.IMO Swimming fitness level can differ from land fitness level, I can swim for miles, but have not run for years due to injury so if I stepped on a treadmill i would collapse within about 30 seconds. Its what you get your body used to doing you will find the easiest! The more swimming the esier it becomes but dont stop training for the other parts!
When swimming, I swim with a triathalete(sp) and a marathon runner. The triathlon guy joined upto a bulletin board solely for triathletes, I will try find out which one for you when I see him tonight.(oh and good luck
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