Thanks - that helped alot.
When I goggled the tools I found a good diagram.
I was able to get my Makita impact driver in there and pull out the center bolt then remove the disc/hub assembly. It looks like a little harmonic balancer. On mine the rubber joint is torn up and melted so the center hub just spun. That was the smell I smelt...
I guess I'll try replacing the hub and see what the compressor sounds like before I pull it.
Anyone else been down this road?