(a) The department may establish criteria to determine whether an unladen lift equipment motor vehicle that because of its design for use as lift equipment exceeds the maximum weight and width limitations prescribed by statute is subject to registration under Chapter 502 or eligible for the distinguishing license plate provided by Section 502.146.
(b) Notwithstanding Subsection (a), a vehicle authorized by the department before June 11, 1985, to operate without registration under Chapter 502 may not be required to register under that chapter.