Pininfar Pontiac Kammback wagon

Speaking of Bill Mitchell, wasn't he retired by the time the Pontiac Firebird Kamm back (maybe it was called Type K) wagon prototype was assigned to Pininfarina? So does that make it a Delorean baby? Was that car steel or aluminum? Weren't there a total of three made> One source on the net says 1979 ws the year it was made but another says 1985 when Eric Dahlquist wrote about it in Motor Trend. I guess some private company tooled up to make the conversion kits but somehow they weren't as popular as people figured. I guess home-grown customs don't match the quality of PF. Has the original surfaced at an auction recently?