HT, of course.  I was thinking 'HT onwards had the ABS plastic grill', but that was only belmont and kingswood.  HK had holden written in the bottom, whereas the HT had the middle badge.  
I find it silly they route so many things through 1 fuse.  In the old wheels magazines there was the regular column 'Dirty Wheels" - the writings of a motor mechanic.  I think it was Bill Tuckey's Brother writing under a pseudonym.  
They had a 928 Porsche with flat batteries - no alternator charge - rip out the difficult to remove unit, only to find no issue - turned out it was a blown charge indicator light on dash.