Instrument ground school does not teach you how to fly a specific airplane -- it teaches you how to use instruments which could be found in any airplane. A VOR or HSI will function the same in a fuel injected C172 as it will a carburated PA28. There are specific courses you can buy online that will teach you how to use specific models of GPS, but you're not likely to find that within an instrument ground school course because it's by nature trying to teach to the masses.