I had the same set-up you are talking about, except a 1960a cab (not sure if that means anything). It is hard to get cleans because there is no real clean channel, you just gotta turn the gain down until its not distorted. The 5150 has more gain,distortion, and balls than you will probably ever need! (thats why I sold mine, it was a little too much to have, when playing in small clubs. Not sure about any mods that you would want to do to the amp, just plug in and start tweaking!
btw it won't make you sound like eddie lol