A thin grease coating in the hub and dust cap will prevent rust. Especially brand new replacement parts. These components operate at a higher temperature which may create moisture in the hub that was contained in the air in the hub. That moisture in contact with bare metal will cause rust. More grease than a coating loaded into the hub or the dust cap isn't needed.
1966 Mercury Park Lane 4 DR Breezeway 410 4V, C-6, 2.80 - Streamless.
1966 Lincoln 4 door Convertible 462 4V 1971 Ford LTD Convertible 429 4V Phoenix ~ Yeah it's hot however it's a dry heat!