That's true, I agree with you in principal, but the fact is that they did do a few of these rare specials, using bits from the GM international parts bin like power window switches from a US 2-door. Door trims would be a piece of cake in the Holden trim dept by simply fitting a switch where the normal winder goes.

When I had my van back in the late 70's, my milkman had a HX one-tonner in black, with 308/T400 with a factory fitted Statesman front, GTS guards, air-con, pwr steer, electric windows, GTS dash (and a plastic floor mat instead of carpet). It was all GMH built. They whinged and bitched about it when he ordered it, but he eventually got what he wanted.

All of these "unicorn" cars are one-offs, but they DO exist.

My Dad's best mate used to be the fleet manager at Suttons Motors Chullora back in the 70's/early 80's, and they also did a bit of "Dealer Special Option" stuff for prominent customers.

Just because something wasn't on the options list for a particular model didn't mean you couldn't have it, but it probably depended on who you knew.