Same guy that is selling the Uni tail light housings also has the tail light extension housing listed.....
https://www.ebay.com/itm/1961-1962-1963 ... Fz&vxp=mtr
NOS LWB Unibody RH Tail light extension panel on ebay
Re: NOS LWB Unibody RH Tail light extension panel on ebay
Old new stock still surprises me.. Its nice the guy knows the part is for a long box..