Either double the acoustic track exactly and pan each hard r/l, or use a capo for the 2nd part, playing a slightly different chord configuration (this will minimize phasing issues if the track is listened to in mono). Again, pan hard, or almost all the way. I EQ both tracks essentially the same and usually cut most of the lows off my acoustic tracks for a full band mix (up to 200-250Hz). I don't like to boost any upper range EQ, as it can really make them sound thin and harsh. You may want that "clicky" pick sounding strum that is so prevalent in alot of pop/country music. There is virtually no bass on those types of tracks, just enough upper mids to give the "impression" of an acoustic guitar.
The key, I think, is to make sure each instrument/voice has a specific place in the mix in terms of frequency range, panning, and depth. Here's a good article on making frequency cuts/boosts:
http://www.digitalprosound.com/2002/03_mar/tutorials/mixing_excerpt1.htm
The 2 songs in my sig were both done with doubled guitars panned left and right. I'm still learning about all this, too, so they aren't perfect, but should give you an idea of what I'm talking about.