No need for that - just fill the charcoal ring full to the rim (and a little beyond) from the charcoal bag, Minion Method your start and you should be good to go!
I used a full 15 lb bag of Stubbs Briquettes this weekend - pretty much the full bag in the charcoal ring (it was a little heaping), tossed some chunks on top scattered around, then lit about 12 briquettes in my Smokey Joe with a weed burner.
Lit on top, let it sit there for 5 - 10 minutes with the smoker unassembled while I pittered around getting things ready, then assembled the somker, put the meat on and watched the temps for a while.
WSM settled in at 240 and stayed there for 14 hours until I took my butts off. At one point, around mid-night, the temps edged up to around 250. I touched the vents a couple of millimeters and in 30 minutes or so she settled back to 240 and stayed there until I took the meat off. I still had enough charcoal in the bowl after the fire went out to cook some burgers on the Smokey Joe!
Pat