Can't get it to idle right!

The usual culprit is a vacuum leak of some kind. The engine drawing more air but less fuel will cause it to run up and down as it tries to "balance" itself. I would start with that. From there the next choice would be carb. Depending on how often and the last time it was run there could be problems with it. You'd be amazed what gas today looks like in just 6 months of sitting inside a carb.