You did push the pistons full back into the calipers before installing the new pads, right? That should provide enough room for the new pads.
There seems to be a widespread misunderstanding about how hydraulic brakes work which leads people to think that removing some fluid will make more space for pads or set the pads further apart.
You cannot reduce the amount of fluid in hydraulic brakes, because it is variable and has a reservoir in the lever units to draw from. Fluid is drawn in to compensate for brake pad wear and gradual advancement of the caliper pistons. Also, fluid can move back and forth as the temperature changes and the fluid expands or contracts.
The way this works is when the levers are at their 'at rest' position the reservoir is connected to the lever cylinders by a small hole which allows fluid to move in or out. The first part of the travel of the lever piston in the cylinder cuts off that hole to the reservoir and seals the system. Then, as the lever piston applies pressure the caliper pistons are pushed out to apply the pads against the rotor.
The small hole connecting the lever cylinder to the reservoir also allows you to push the caliper pistons back in to the calipers when replacing the pads.