This was 457 Squadron RAAF which was transferred back to Australia. I don't think they had Jeeps or were called Grey Nurse until they were here and re-equipped with Spitfire VIIIs.
By that stage (1944) the shark mouth was a popular thing. For those not in the know a Grey Nurse is a type of shark.
Here's a pic of the Temora Aviation Museum's Spit painted as a 457 machine with the RAAF Museum's Mustang.
