Thinning and cleaning: Interlux Schooner Varnish?

Hi Folks-

Before tackling my first finishing project (Kaholo 14), I need some advice.  I'm intending to use my HVLP sprayer for the job, so I need to pick the right solvent to clean up the sprayer, and potentially, thin out the varnish bit prior to application.

I contacted Interlux, and they said use their "Special Thinner 216."  Fair enough, but not exactly something I can buy locally.  I pressed them for more "generic" options, and they said to use xylene. 

Okay, so now my question: anybody have experience using HVLP with the Interlux product, and more specifically, cleaning and thinning?  Xylene or otherwise?

Thanks for any suggestions,

Jim L.