In '68, there were a couple of 'engineering exercises' that made their way out into the world. One of them spent a great deal of time at ATCO raceway in Jersey. As for the '69 H/O convertables, 3 was the official number, but there was a story behind that. Hurst kept one car for engagements east of the 'big muddy' one on the west. The car for the west engagements was involved in an accident in New Mexico and totaled out. The powers that be had the 3rd one built to replace the totaled unit.
My friend in Iowa has one of the '69 units and they are in process of finishing up the '68 unit that was at Atco. The '68 is being finished as it was intended, BIG metalflake gold with black accents and Hurst wheels all the way around. The '68 still has the experimental 455 with a dial back distributor. The other '69 is in Cali, rotting away under a tree!