Before you attempt this I recommend that you understand the not insignificant differences between epoxies and paints, even those that are catalyst-cured.
Epoxies are not actually "thinnable" in the sense that paints are. Epoxies are not soluable in alcohol; epoxy molecules are merely suspended in alcohol. When you add thinning agents such as denatured alcohol to uncured epoxy, the liquid alcohol disperses the unreacted epoxy 'A' and 'B' component liquids and apparently "thins" it. We see this as reduced viscosity.
When the epoxy 'A' and 'B' components finally meet each other and combine, react and solidify, the alcohol liquid is still present - as liquid alcohol, not thinned epoxy. As the epoxy hardens, microscopic liquid-alcohol voids are created between hardened particles of epoxy. The result is NOT a solid mass of epoxy with the expected strength, but a weakened structure, joint or surface film.
I propose that you do not attempt to thin epoxy for spraying. It can be sprayed, but only with a system designed for high viscosity liquids. Oh, and you'd better be quick with disassembly and cleanup of the spray system. Otherwise, spraying can get very expensive. Rollers are significantly less expensive...
Paul Miller in Memphis, TN
"Yeah, I had lunch with him last week at the Cracker Barrel out on I-40."