Okay I have no idea as to whether this will work or not. I cannot hook up the guitar at 11 pm at night to compare with my guitar amp.
Right why not try loading a multiFX and try to emulate an amp using effects, I mean thats all a Pod does really; reproduce the tonal characteristics of an amp model.
The signal chain as follows;
First distortion or overdrive a better option I would go with TQ Drive play about with the presets. Then maybe a soft clip, and compression as your ears prefer.
These effects will be mono so hook up the outputs of the multifx to the masterverb, masterverb you ask?
Its a slightly flawed theory but surely a guitar cab can be thought off as a really small space, so try setting the room size values quite low on the MV, and set the ER reflections to something like ROOM1
I'm sorry I'm not being more specific, this is an experiment remember!
TQdrive and masterverb have equlisation options to play about but keep in mind that a guitar amp has a rolloff below 50hz (most amps don't get lower ) and also have a high eq rolloff above 2 or 3 khz
Also try cutting in the 200hz range if the sound becomes muddy.
Ok there are a lot of things that I have overlooked, such as recreating open back or closed back amps, mic proximity etc.
But I'm no expert thats for you to figure out!