Daniel from Mulgo sells a 110ah battery that fits perfectly next to the starting battery and you can also fit his dual battery kit in the same space.
https://www.aulro.com/afvb/images/im...013/05/475.jpg
https://www.aulro.com/afvb/images/im...013/05/476.jpg
I also fitted buss bars for winch etc to keep the excess leads off the battery terminals
https://www.aulro.com/afvb/images/im...013/05/477.jpg

