tires…what should I do?

I in installed some awesome m20 kore wheels. I mounted some kanati mongrel 28x10x14 tires. My take off big horns measured an an actual 26 inches. My mongrels mounted was 26 and 3/4. i am pissed. Efx motor mtc actually measure up to actual height?. Lobe the looks of the tire. Thought about the gbc dirt commander in a 27×11 because I hate the skinny rear tire. But will it measure actual 27 inches?? I didn’t want a 30 in tire so I didn’t have to buy a clutch kit bc I already have a high lifter 4 in lift. But if a 28 inch mongrel isn’t even 27 inches? What does a 30 measure.? I got burnt once and have 5 miles on these tires and want something else. Help!!