In addition to the other equipment required by this title, including §§ 22-203, 22-204, 22-205, and 22-206, the vehicles mentioned in this section, when operated on any highway, shall be equipped as stated in this section. All required lamp equipment shall be lighted at the times mentioned in § 22-201.1 of this subtitle. The reflectors elsewhere enumerated for these vehicles shall conform to the requirements of § 22-211(a) and (b) of this subtitle. Buses and trucks 80 inches or more in overall width shall have: On the front, two clearance lamps, one at each side, and on those manufactured or assembled after June 1, 1971, three identification lamps meeting the specifications of subsection (c) of this section; On the rear, two clearance lamps, one at each side, and after June 1, 1970, three identification lamps meeting the specifications of subsection (c) of this section; On each side, two side marker lamps, one at or near the front and one at or near the rear; and On each side, two reflectors, one at or near the front and one at or near the rear. Trailers and semitrailers 80 inches or more in overall width shall have: On the front, two clearance lamps, one at each side; On the rear, two clearance lamps, one at each side, and after June 1, 1971, three identification lamps meeting the specifications of subsection (c) of this section; On each side, two side marker lamps, one at or near the front and one at or near the rear; and On each side, two reflectors, one at or near the front and one at or near the rear. Truck tractors shall have on the front, two cab clearance lamps, one at each side, and after June 1, 1971, all of these vehicles shall have in addition three identification lamps meeting the specifications of subsection (c) of this section. Motor vehicles, trailers, semitrailers, and pole trailers 30 feet or more in overall length shall have on each side, one amber side marker lamp and one amber reflector, centrally located with respect to the length of the vehicle. Pole trailers shall have: On each side, one amber side marker lamp at or near the front of the load; One amber reflector at or near the front of the load; and On the rearmost support for the load, one combination marker lamp showing amber to the front and red to the rear and side, mounted to indicate maximum width of the pole trailer. Whenever identification lamps are required or permitted by this title, they shall be grouped in a horizontal row, with lamp centers spaced not less than 6 nor more than 12 inches apart, and mounted on the permanent structure of the vehicle as close as practicable to the vertical centerline. However, where the cab of a vehicle is not more than 42 inches wide at the front roof line, a single identification lamp at the center of the cab complies with the requirements for front identification lamps.