My advice on Wylds Craig - don't do it in summer, there are @#$@ loads of snakes.
Track start is on the Tiger Road, which comes off the Florentine Road, which is off the Gordon River Road. You need to go well past the Lake Rhona turnoff if you know where that is. Do a search for Wylds Craig on listmap on the 1:25000.
No sign at the track start, just a little pile of rocks on the left with a stick poking out of it IIRC. Track is easy to follow, not really anywhere you could wander off and get lost unless it snows.
Apart from that, it's probably in the realms of 6 hrs depending on your speed, think it took me and Az around 6. Not really much to see on the way up but the view from the top is good.
[EDIT: AAAAAARGH! Beaten!]