Oh, let's see how I should say this..............
azmark: I usually keep at least two eyes open; sometimes I may 'squint' with my weak eye to focus my sight picture on the target. True the Army Manual sez to keep both eyes open but if that doesn't work for you, squint or something to focus your dominat eye. While you may lose some acuity with a one-eyed focus you may actually gain acuity if your weak eye has more of a negative than positive effect. I try to get a good sight picture first and then keep my front sight on the target. When I hunt with a pistol I wait for the critter to get into my sight picture rather than trying to chase it with a front sight.
Montveil - That is why they don't have any left handed riflemen or machine gunners in the United States Army and I was probably one of those who would absolutely NOT let you shoot a M60 Machine gun left handed. M14s and M16s have been known to kick brass back right into a forehead and eyeball. That being said however I'll bet your left hand shooting with the 45 was better than with your right hand......
Curtis - heck man, learn to shoot southpaw. I occassionally go southpaw and am usually pretty happy with the results, and it's a lot fo fun. Sometimes I even shoot two-handed and that is a real ball. If you learn to shoot left handed and as a result carry left handed, even with your learned right hand dominance you would have an upper hand with concealability (just a thought). Mikey.........