Of course there is, open your save in the hazard save editor. Go to the Block tab and extract your PSIN. Open the PSIn block in any hex editor, preferably HxD. Make sure you know your license plate. Press Ctrl+F. In "Search for:" enter your licence plate. And change "Datatype" to "Text-string". And hit search. It'll highlight a few numbers. Change the number before the first highlighted number from left to right, to 05. Save the PSIN block and replace it in the save editor. And save. Voila.