Ok, if that left part is a strummed guitar part then it needs some serious work as all I'm hearing is the click of the plectrum on the strings and no actual notes in there. Try attenuating the clickiness with an EQ (eg. low pass at 2KHz) and compress the track as well.
Both tracks will need to be brought in towards the middle - they don't sound 'slightly' panned, they sound almost hard panned. Start with maybe 10% left, 10% right. Send them to the same stereo reverb to anchor them in the same virtual space.
I actually just muted that strummed bit and tried the other things you suggested, it sounds 100x better already. I think he had panned them slightly in recording which I compounded by panning them myself. I think it was too long listening to the same thing and I could no longer trust my ears. huge thanks again!