A quick Google search will get you a ton of results while you're waiting for answers:
From William over on CRG.
"Rear axles were painted as an assembly; cover and brake drums in place but no lines. Pinion flange was masked. Paint was a glossy black. Yes the drums were black too.
Leaf springs were not painted. The forging process left them with a mottled black-grey finish."
I left my springs natural and this is what I did to my posi:
Here's a survivor 69 Z:
