I posted the XJ90 a gazillion years ago and I really liked that car but was intrigued as to what had become of XJ80. Recently some of you may have seen it's reveal on FB c/o Chris Ruddell a former Jaguar designer.
My understanding was that GM was about to buy Jaguar and the developed the XJ80 (hence the proliferation of GM parts on early XJ40's, a legacy which continued with the alarm system) but the the government stepped in worried for the safety of the Bedford truck division and vetoed the deal.
I'll let the pics do the talking.
XJ40 1978 George Thomson Doug Thorpe-