Get your sound where you like it, stick a sm57 in front of the speaker and record that. Shudder in terror at how bad it sounds.
Turn the gain on the distortion down and move the mic around and do another 75 test recordings (moving and angling the mic in half inch increments)- pull it back and forth and get a good feel for how the proximity effect will go from muddy to fat on the low end. Do this long enough, and you will note the subtle differenced that mic placement can give.
Tweak the amps and pedal and guitar for the recorded signal, not what you hear live.
Keep in mind where the guitar will sit with the rest of the instruments, you may want to roll off the low end so the bass and kick and sit there, and gate any hiss and that sort of thing.
Good luck.
Daav