Someone on here once suggested putting a bead of high heat silicon about an inch up from the edge of the lid, this will keep the drips inside the barrel. I don't like the idea a foreign material right above my food surface, and if it ever came off it would be in the bottom of the barrel.
I also saw someone who welded a ring on the inside that works the same way. That is the ideal way if you have access to a mig and someone with some skill.
My drum is SS, so i just wipe it down when needed.
Out of the Ashes BBQ Team
"Keepin' the Bar in Barbecue"
WSM 18.5" & 22"
22.5 in Weber Kettle
SS UDS 1.0