2006 Sebring convertible. A couple of the top joints need greased. What's the best way to do it?

 

Very carefully.

Actually, the shop manual makes no mention of either the need for lubrication or the method. Depending on which joints you want to reach, you may need to partially remove the headlining.

I would think that oil would stand a better chance of getting in where it's needed than grease would. But a light oil like WD-40 is more likely to wash out whatever grease is in there and be counterproductive in the long run. I used to have (many years ago) a "pump oiler", it was an oil can with a built-in pump. It had a long nozzle that would reach in where the oil was needed. Squeezing a finger trigger pumped oil out the nozzle. It was very useful for re-filling the rear shock absorbers on my 1967 MG-B GT. You'll want something like that to get up into the joints in a very controlled fashion so as not to get oil all over the place.

Come back and let us know how it comes out.