Ok... the 2 inch rule is not a myth... but it was scrapped and updated a good few years ago now in Vic anyway... pretty sure all states have conformed as it was a ADR regulation so across the board... but get a modification guide and look it up to be safe.
Now... the new rule... in VIC anyway... it that you can only increase the width of the wheel by a max of 25mm and the overall diameter of the TYRE by upto 15mm.
So 19's are fine so long as you have the right profile tyre, the right load rating and it doesn't scrap or foul any of the body or suspension in its operation.
So if you're scrubbing you need the guards rolled.
I had 19's on my VX II S back in the day and i needed to roll only one guard... which was the Left rear guard... but I did have SSSL springs in it which didn't help.
Alot of people have fitted 19's without any issues so as long as you get the right width and offset... you should be sweet.
As i said... confirm the regulations in your state by getting your hands on a modification guide but if its the same rules as VIC, you're apples.
Hope that helps and good luck