1994 Buick Roadmaster Owner's Manual - Page 215

Put the flat end into the notch and carefully pry off the small cover. Remove the lock nut by inserting the key wrench into the hole inthe center of the wheel cover and turnit The counterclockwiseto loosen the lock nut completely. wheel cover 'can be removed by hand-- do not pry it off. Now you are ready tostart using thejack and wheel wrench to raise your vehicle.