We did these two mountains the Sunday before last. I tried a different route up Mt Patrick to the one recommended in the Abels book - a route that proved to be significantly shorter (and thus faster). There is a LOT of new roadwork around the area where parking is suggested. A GPS device really helped with the driving, even if not the walking For a full report see natureloverswalks.blogspot.com
I went looking for a way in a couple of years back, but every road I found was signed as being closed for some sort of work on one of the lakes - Arthurs, I think.
"Mit der Dummheit kämpfen Götter selbst vergebens."
If you read my blog and phone Imogen, she'll give you a key that opens all gates and then, yes you're allowed in. She's a very friendly lady, and although she doesn't own the property, is in charge of who is allowed to go in. (I think she said the owner lives in Denmark!) She understands bushwalkers and their whacky need to climb hidden mountains.