Well, lemme give this one a slap.
Conservatism is the idea that each person is the chief architect of his or her own life. That expansive government is a direct challenge to that primary ideal. That excessive taxation is tantamount to theft. And that, while a societal safety net makes for a healthy population, cradle to grave entitlements do not. That National Defense is at least as important as internal infrastructure and that rampant government spending is an anchor that weighs down a robust and healthy free market economy.
A plutocracy is the notion that the elite, or ruling class, is to be made up of the wealthy and powerful. Which is pretty much what we have in America now except that is has a well worn veneer of 'democracy' covering most of it.
I see vast differences in the two.