(a) Except as provided in paragraph (c) of this section, each final-stage manufacturer whose manufacturing operations on an incomplete automobile cause the completed automobile to exceed the maximum curb weight or maximum frontal area set forth in the document specified in §529.4(b) and furnished it by the incomplete automobile manufacturer under §529.4(c)(1) or by the last intermediate manufacturer under §529.5(b), as appropriate, is considered the manufacturer of the completed automobile for the purpose of the requirements of Title V and rules issued thereunder, other than those in part 537, Fuel Economy Reports.

(b) Each final-stage manufacturer that becomes the manufacturer of a multistage automobile under paragraph (a) of this section shall, within 10 days after completing its manufacturing operations on that automobile, send written notification of its exceeding the curb weight or frontal area maximum to the Administrator of the Environmental Protection Agency and to the manufacturer previously considered under this part to be the manufacturer of the automobile.

(c)

(1) If the final-stage manufacturer becomes the manufacturer of a multistage automobile under paragraph (a)(1) of this section, that manufacturer shall prepare a new fuel economy label for that automobile in accordance with 40 CFR part 600.

(2) If the final-stage manufacturer places the portion of the body including the windshield and front seat side windows on the incomplete automobile, that manufacturer shall attach the fuel economy label furnished by the incomplete automobile manufacturer under §529.4(c)(2) or by the last intermediate manufacturer under §529.5(d)(2) or the fuel economy label prepared by the final-stage manufacturer under paragraph (c)(1) of this section, as appropriate, to that automobile in accordance with 40 CFR part 600.

(3) The final-stage manufacturer shall attach to the completed automobile in accordance with 40 CFR part 600 a fuel economy label identical to the label that is required under this part to have been prepared by the manufacturer considered under this part to be the manufacturer of that automobile if:

(i) The portion of the body including the windshield and front seat side windows was added to the completed automobile by a previous manufacturer;

(ii) The final-stage manufacturer's manufacturing operations do not cause that automobile to exceed either of the maxima specified in paragraph (c)(1) of this section; and

(iii) That fuel economy label is not on that automobile when received by that manufacturer or is removed from that automobile while it is in the possession of that manufacturer.