That sounds like a fine idea. I've got an 18000BTU unit with a blown compressor that I'm considering doing this with. Actually came to garage journal to investigate and see if I was the only one with that idea.
I just bought a Campbell Hausfeld 60 Gallon 3HP (made in USA, decent warranty, national chain) for 399.99 at Tractor Supply. I just came here looking for ideas for plumbing it in.
I look forward to being able to recommend it after I've put it to good use.