Hi Paul.
Iv'e heard 2LT here in Melb fairly audible after 11.00pm at night. Now I know which one was always fighting with 7AD when that was on MW. 
On 558 6WA could always be heard late at night here too as it was easy to null out 7BU. 4GY may be more of a challenge but I'll be listening for it. 
Any news about 7SD 540KHz moving to FM? 
Cheers. Dan.