Having proper leverage is actually the least important part of the equation when it comes to removing tight fitting tires, especially tubeless tires. Here are a few tips that should make the job easier:
There is a trough or channel in every rim. It exists so the tire bead can be pushed down into it to make removal possible. When you start removing the tire, push one of the beads into this channel while leaving the other one fully seated. This will ensure that the loose bead will make it all the way down to the channel.
Start prying the tire off of the rim at the valve. Because the valve takes up a good portion of the rim channel, you shouldn’t fight it by starting on another section of the rim. Once you get a portion of the bead out, you can usually hold it with your hand and use the lever to get at the next section. Having two tire levers is helpful, but not necessary.