Grease, lard, Crisco, doesn't matter. Just don't use motor oil. As far as the chimney, congrats on the purchase but don't load that thing up to start a UDS. You need 8-12 briqs lit. That's it. If you throw a whole lit chimney on top of your basket you'll never get the temp down low enough.
Weber Imperial Sequoia (restoration in progress)
Weber Platinum (The Green Lantern)
Weber OTS 22.5
UDS (with more to come)
Old Smokey ES (A gift, don't buy one)
Humble member of the Society for the Preservation of Authentic Royal Magical Rare Kaskaskian Peppers
Honor bound to protect, prepare, and serve