Schedule 8, by inference, allows removal by the pilot of non structural cover plates and fairings since this task is incidental to the others specfied (see item 16 in CAP 42).
To go back to Dash 8's original question, I would have thought that any Inspection involving entry to an aircraft by a CASA operative, authorised or not, in the absence of the owner or person responsible for the aircraft, had better be followed by:
(a) The written notification, left either in the aircraft or some other convenient location, containg the name, position, date , time and purpose of the inspection together with details of anything removed, or the result of the inspection.
(b) A follow up phone call or email if practicable.
Furthermore, the only "inspection" I can think that could reasonably be made by CASA would be to:
(1) Check that the aircraft is properly immobilised as required by law.
(2) Examine either for a leak or an apparent external defect.
If they want to see the maintenace release or other documentation they will be out of luck if its my aircraft because when travelling I always take all of it to the motel for security and the aircraft is locked anyway.
There are laws against tampering or interfering with an aircraft and if you ain't authorised that is what you are doing whoever you think you are.