@cinmur- I don't know how much coal they use, but maybe try starting with 8-10 lbs for long cooks and go from there. Remember it's not rocket science, it's oil drums, meat and fire. Wait- after reading entire thread, maybe not...
UDS'-55&16, Akorn, Bar-B-Q Kettle, Drum Grill, miniWSM, cobweb-covered gasser. I'm JD.