(3) May consist only of alphabetic or numeric text on a plain background and may not include any graphic, pictorial or photographic images.

C. The display may comprise no more than 50% of the surface area of a changeable sign.

D. No more than one changeable sign with 2 sides is allowed per lot of record.

E. Changeable signs may not be located so that the message is readable from a controlled-access highway or ramp.

F. The highest point of the display of a changeable sign may not exceed a height of 25 feet above either the centerline of the nearest public way or actual ground level adjacent to the sign, whichever is lower.

G. Changeable message board signs existing in accordance with the requirements of former subsection 11 continue to exist if the signs:

(1) Are reasonably incapable of being modified or reprogrammed to comply with this section as amended; and

(2) Are not replaced, substantially rebuilt, reconstructed or repaired beyond routine maintenance.

H. The size, intensity of illumination and acceptable rate of change between the time display and the temperature display of a time and temperature sign must comply with rules, policies or guidelines adopted by the Department of Transportation. Rules adopted pursuant to this section are routine technical rules as defined in Title 5, chapter 375, subchapter II-A 2-A. Time and temperature signs erected prior to September 29, 1995 need not comply with those rules, policies or guidelines.

I.__A municipality may adopt an ordinance that is more or less stringent than the minimum standards established in this subsection and in rules adopted by the Commissioner of Transportation to implement this subsection.__A municipality that adopts an ordinance with provisions that differ from statewide standards shall administer and enforce that ordinance.__A municipality may not adopt an ordinance that