geez, emg's, overdrive + engl?
what is this, gain central? you're a bad influence, nick, my man! :lol:
EDIT: also, don't discount a clean boost, that can give you a slight boost, remain transparent, and still sound good.
From what I can remember from trying in the shops, for a smoother tone, I normally put the bass and mids around 7-9, and the treble around 3-4. presence low-ish (not over 5). that's for the two higher gain channels... hopefully the two cleaner channels still sound good at that.
then just increase whichever one of those is lacking (or vice versa for whichever is too strong). Engls are pretty easy to eq, the knobs normally do what they say.
Of course, as nick says, that'll get you my tone, not yours. Handiest thing to do is to just set everything to noon, and again increase or decrease as required. Also, only work on one knob at a time, so you can hear what it's doing to the sound.
I haven't used an EQ with my engl yet, I don't really need one. My guess is though that increasing the lower mids and taming the treble a little might work wonders for it. make it sound a little more like a mesa.