So are you taking your boat and beach launch trailer into shelter bay? And then wanting to you out through the heads? It can be done, but by jeeze they get some waves up those cliffs! I'd only go that way if you were 199% sure it was going to be glass conditions 

 Did it in October in a 17ft Caribbean in 2.5m seas, handled it like a champ, you'll be fine

 will dictate whether you go out or not. The wind tends to come in from south pretty quickly early afternoon so we would troll first light when its calm around black rock (approx 3-4km's north of the opening to the ocean) for mackies then go south past steep point around 15-20km for demersals so if wind comes in earlier than expected your not having to plough your way home. We did also troll south from steep point early in mornings but only picked up a couple of mackies, dont know why but they hang around that black rock area most of the time.  It gets pretty sloppy and shitty pretty quickly from our experience so keep that in mind  good luck with the sharks!!!