I did mine fairly recently, just took them all off. Gave it a quick sand, basically taking off some of the older drying paint that was peeling and then just sprayed it a few coats with a cheap can of black paint. Actually came up real nice. Tip is to get some old wire coat hangers, untwist the top and slide a wiper onto it and that works really well to hang it to try and so you dont have fingerprints all over it.
Shouldn't have to worry about missing some spots with the joints. With a spray can you should get it in all the gaps
With the front wipers I took the blades off but with the rear just masking taped over the blade.