I have a couple of mates work for Hawker Pacific so my comments are based on their observations only .. worth a try I would think.
You could approach any of the various MRO or defence related bases and ask for the site maintenance manager. I believe that the KingAir operations (East Sale and Townsville) would be inclined favourably to assist.
Five days is fine . .but several weeks over your school vacation period is much better so you can get to see more of what goes on.