you best option is to remove the toilet you will get a better looking seam where the floor meats the base of the toilet and if at any time you have to replace the toilet you do not have to worry about finding one with the exact same base. Rmoving a toilet is easy simply unhook the water supply loosen the bolts on eaither side of the toilet at the base and have someone help you lift it out of there. When replacing it make sure you replace the wax ring.