I thought of a couple of extra ideas for you and they are:
1. Replacements for the four metal covers that are screwed to the inside of the tray on the utes as most of the original metal ones are dinged up. Some carbon fibre look ones would be great.
2. Maybe a new version of the little vents that go on the side of the utes.
3. A rolled pan type thing (like all the minitruck do) to smooth out the rear look of the utes and extend it a little. Perhaps it could include little bumpers and use the existing bumper holes as a connection point (a bit like the rear apron on a commodore ute I suppose).
4. I've been watching a few US inspired car DVD's lately and I've noticed that they are making some nice front spoilers for older cars that include formed holes for a couple of driving lights. Makes them look factory.
I'll PM you as I'm interested to see anything your making. Good luck!