Nice tune Harry!
Rich, I imagine you've been through
this post at Must Reads. And the first link there points to a thread where I talk about my SF-2 settings. The post is from three years ago, but basically I still set mine up following the same ideas.
In thinking about your questions however, trying to get a series sound on an Epic, you might try this.
Set the bass B and T to flat. Set both filters to low pass. Set the first similar to the settings I have on my left channel. On the second filter however, turn the filter setting all the way to 6KHz, then turn the damping ratio up to 9. That should give you the series sparkle of having the filters open and and Q's on. To really hear the effect, turn the direct gain and the first filter gain all the way down so that you're just listening to the sound through the second filter. Then mix in the first filter, essentially adding in low bass, and mix in the direct gain, the dry signal, essentially adding mid. Reducing the damping ratio from 9 to 6 should give the same effect as switching the Q switch on a Series I from 9 to 6. Once you have something you like dialed in, you can then adjust the bass and treble controls on the instrument to vary the tone for different songs or passages within songs.
Still following on from the last paragraph, leaving the second filter maxed out and turning your attention to the first filter. Turn the direct gain all the down again for the moment. Open up the damping ratio on the first filter to 9 as well, and start bringing up the frequency control until you get a mid low growl. This would be similar to having one filter on a Series I open and boosted, and the other filter partially open and boosted. Adjust the two filter gains for a good balance, and bring the direct gain back in to taste.