Spent a good hour trying to get the brake caliper bracket back on with my new rotors, when we finally realized the disc is much bigger than the one that was previously on my car. The newer one is oem spec for my make/model. Should I just return these and find a smaller rotor or replace my calipers?
You got the wrong rotor. Cars often have different rotor sizes depending on the trim level or model year, so it might be OE spec, just the wrong OE spec.