There is no issue with using the gauges in this manner for personal use. If I were to send the gauges to someone else or didn't pay for them initially that would be an issue. I bought the Carenado Mooney and modified it somewhat to work in my cockpit, it's really not much different from adding a repaint to the original model. I have been developing freeware aircraft for 5 years and have seen my work get altered and re-distributed in ways it was never intended, it can be frustrating to say the least.