would be very few of those original front guards left. I think i read somewhere that civillian units also were initially fibreglass then metal. This would make a lot of sense since the retro fitted steel guards on the army units would coincide with the introduction of the stepless steel units on the '64 - '67 civvy AACO's.
My models of the Mk3 will have the stepless guards as that is how they appear in all photographs of them. I noticed also that some seem to have a slight cutout between the front of the guard and the bumper while others do not. Mine will have no cutout but it can be put in by the model assembler if desired.

Mousey