Need a song arranged and mixed

One of the artist/producers is really great at creating songs but we think it would be better to hand the 'finishing' off to someone else. Someone with a great pop arrangement sensibility. And strong mixing skills. The artist/producer is a Latin grammy award winner. So the quality is there. We just need to find a solution to our workflow. Where we can give them the track and have it go from an 8 to a 10. :}

Additional info:
I don't need the song mastered. I need the mixer to do some editing, time aligning and vocal tuning before mixing. I don't have a hard deadline for this. I'm interested in working with a very experienced mixer. The song has somewhere between 10 and 30 tracks recorded that need mixing. .