My Strat came with a Mustang setup, but on my Boulevard, the Mustang seat moved me forward, and into a more upright position than the stock seat. Unfortunately, on the Bully, this caused cramping in the hips for me. I do not know why, it just did. The angle on the Strat is much different, and just feels far more comfortable. I can ride for three hours or so before I have to get off and stretch, as opposed to maybe an hour and half tops on the Bully.
Also, you can try moving the bars slightly, by loosening the bars in the risers, and rolling the ends up or down.