I was in the same boat as yourself, cleaned them with Coke then Jizzer then started with a wire brush! Done a few to see how they would out but was got talking to a lad who refurbs wheels and told me I was wasting my time unless I painted them after....
I had 30 bolts per wheel and 6 wheels so wasn't to keen on cleaning them anyway!

Took a pic the last day for ya
(New one, Cleaned and wire brushed old one, old one)