Good info Detective Komodo
So the $390 battery is that 100AH or 200AH? Didn't realise the ventilation was an issue, is that for overheating reasons? I keep coming back to the weight issue though unfortunately.
I was at work today and checked what auto electrician they use, so will give them a call, probabaly not till early next week. (Darn work constantly gets in the way of my holiday planning!!)
I will have a look for the battery box at Repco sounds good.