This is a tricky question, I've found you can't possibly plan every place, but having a general "must see" list will help us to get a general travel route.
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Hours in normal car speed, haven't calculated towing a van.
Gold Coast > Glass house mountains - (2 hours) 2 nights
Glass house mountains > Malooloobah - (50 mins) 4 nights
Malooloobah > Gayndah (3.5hrs) 1 night
Gayndah > Dululu (4hrs) 1 night
Dululu > Emerald (3hrs) 1 night
Emerald > Barcaldine (3.5hrs) 2 nights
Barcaldine > Mt Isa (8.5 hrs) 1 night (or atay cloncurry)
Mt Isa > Tennant Creek (8.5 hrs) 1 night
Tennant Creek > Dalywaters (5 hrs) 1 night
Daly waters > Katherine (3.5 hrs) 2 nights