Shown below there is a Retriever fuel tank picture form the Lynx & Retriever driver´s handbook. See how rounded if the fuel tank and how it is situated on the vehicle´s frame. I also can not resit the feeling that Retriever has horisontal hadle behind the door while the pictures above shows vertical handle. Also, see the mudguard edging. On the picture above there is quite sharp edge while Retriever has a rounded edge. I guess it is not Retriever. Maybe Crossley?
Happy searching
Jan.