I pulled a toilet, there is an ABS flange that resembles an LP (remember those?) left in a hot car. The flange is fairly flush with the finished floor , not on top. Should I go with a thicker than standard wax ring? I've also read here to place the ring on the flange, then drop in the bowl. Every box I see, it reads to put the wax ring on the bowl first. Placing the wax ring on the flange first appears better to me, but would anyone explain if there is a difference?