Thank you everybody for the replies. I really appreciate it!

I had asked the LBS if I could bring in a parts bike and a project bike and use their crank puller to swap the cranks on the two bikes. They said sure. They mis-understood it that I wanted the cranks left off of this bike, somehow. No big deal IMHO.

I really like the spacer idea. That's all it'll take to fix this, its SO minimal. Except for the obvious sound of it, I don't even notice it when riding.