Motor Manual Magazine Letter to the Editor Aug 1983 issue, MM say some of the GMH Prototypes were Sold to the Public and Harry Firth and Don Holland might of converted some XU1's to V8's for use on the road, heard rumors that HDT/Harry Built a SMP LJ XU1 for Kevin Dennis Motors New Car Yard in Richmond Victoria and Wheels Magazine in Feb 1973 tested a White LJ GTR V8 that Don Holland built for a Customer Geoff Maloney at Max Wright Motors, Penrith Sydney Holden Dealership from advise from Harry Firth.