Hi Banana Slug! I've been up Perkins about 3 times now. The first time I heard about it was from a Ministry of Forest guy that recommend August as the prime month to be there. Every year of course is different, but I've been in July and not been able to get to the highest access by vehicle. You will still get quite high on the mounain. If you are intending to quad up instead of drive, no problem. Have fun, enjoy the view of Waddington!
Appreciate life's simple pleasures