If you loosen up the center allen bolt you can then use an adjustable wrench on the flats of the adjustment to put the arms where you want. Then tighten the bolt while you hold the adjustment bolt where you want. Once set up they are great brakes.
I have fenders on mine, and I just used a zip tie to attach the front fender to the fork - the extra space that allows the fender to drop helps. I had a front rack setup on mine, but it was a kludge.
Photos of yours please - I love mine.