N.H. Rev. Stat. § 259:106-a
"Street rod" shall mean a vehicle, the body and frame of which were manufactured prior to the year 1949 and which has been modified for safe road use, or a replica thereof which has also been modified for safe road use. For purposes of this section, the word "modified" means, but is not limited to, a substantial and material alteration or replacement of the engine, drive-train, suspension or brake system or alteration of the body which may be chopped, channelled, sectioned, filled or otherwise changed dimensionally from the original manufactured body. Any such modification may be made only if said modification equals, improves or enhances the safety aspects of the original equipment so modified. For purposes of this section, the word "replica" means a body or frame manufactured after the year 1949 and which resembles that of the original vehicle and which retains the basic style and dimensions as originally manufactured and whose major components such as grill shell, hood, or doors are readily interchangeable with the original pre-1949 component.
RSA 259:106-a
1992, 214:1, eff. Jan. 1, 1993.