No, you need to add it at the end of a line. For instance, if you want to add liveries to the police cruiser, here's what you should have:
police, police, car, POLICE, POLICE, VEH@STD, VEH@STD_RI1, 100, 999, 0.2345, 0.2345, 0.2, 2, 1.0 ,1, ext_requi+ext_strong+livery