In all honesty, give toy car to a princess (5-2)

I believe the answer is:

dinky-di

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'in all honesty give toy car to a princess' is the definition.
I can't tell whether this definition defines the answer.

'give toy car to a princess' is the wordplay.
'give' means one lot of letters go next to another.
'toy car' becomes 'dinky' (I can't justify this - if you can you should believe this answer much more).
'to a princess' becomes 'di' (Princess Diana).
'dinky'+'di' is 'DINKY-DI'.

Can you help me to learn more?

I've seen this clue in the Sydney Morning Herald.

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