With the OEM Side Steps available from Diesel Freak, stepping over the lip is not a problem.
You can vastly improve the Turning Radius by adjusting the Wheel Stops. Mahindra must set the wheel stops way short to avoid roll overs. Adjust the wheel stops just short of the tires brushing the Springs. It will then turn just fine.
I would bet that the Lip is Structural Support for the body. The Mail Jeep might have some other structural stiffener that is not obvious. Also a Mail Jeep should not have a rough off road life requiring structural strength.
Bob R