sorry but no
The repair tech at my company has been working on shure microphones since the late 60's. He has fixed many a 57 and 58. The micophones may have different chassis, but their circuity is identical. It is the windscreen that causes the differences in frequency response(the small gain in low end), hence the different patterns. However, you cannot put a 58 windscreen on a 57, but you can purchase a windscreen for the 57. This allows the 57 to be used as a vocal mic, but it just dosn't look as "cool" as the 58. I don't understand what the big deal is, the 58 is sold as a vocal mic, and the 57 is sold as a instrument mic. You can use them anyway you please, Shure just designed them for specific tasks. Who cares if they are the same mic. Just deal with it. They are both kick ass mics, and any recording "genius" should own at least 2 of each.