Vehicle Code § 267

A “converter” is a person, other than a vehicle manufacturer, who, prior to the retail sale of a new vehicle, does any of the following to the vehicle:

(a) Assembles, installs, or affixes a body, cab, or special equipment to the vehicle chassis.

(b) Substantially adds to, subtracts from, or modifies the vehicle, if it is a previously assembled or manufactured new vehicle.