Ok I fully expect to be slated for this post, but I am suffering from complete brain melt down.
I started this conversion 10 years ago and totally lost heart in it not far in when we kept having water ingress problems, so just used it as a run around for work
I then built another camper on a different van, but that had loads of faults along with a very unhelpful warranty dealer, so now I have come back to the T6.
Everything on the conversion is going really well, but I am now at the electrics stage, the van was fitted with the factory auxiliary battery, but things have moved on and I now have a fogstar 560 amp Lithium as we cook using induction and have a small water heater.
This is where the meltdown has started, it appears my auxiliary setup is used to power the trailer lighting and sensing, I have 2 extra cables going to the pos terminal, I have one red and a red/yellow that splits in to 2 cables, and then I have the the 10mm positive. I have read loads about how to fit a B2B but a lot of it says the cables to the battery and earth under the seat need to be upgraded, but If I connect the pos and neg to the Victron XS 50amp it will leave those other cables without power.
I'm assuming another way around it, is to leave the under seat battery and come off of that to the XS, but I have read conflicting reports about that also requiring cable upgraded, I could use the original auxiliary to power just the LED lighting.
All the wiring from the XS would be in 16mm.
Any help would be greatly appreciated.

I started this conversion 10 years ago and totally lost heart in it not far in when we kept having water ingress problems, so just used it as a run around for work
I then built another camper on a different van, but that had loads of faults along with a very unhelpful warranty dealer, so now I have come back to the T6.
Everything on the conversion is going really well, but I am now at the electrics stage, the van was fitted with the factory auxiliary battery, but things have moved on and I now have a fogstar 560 amp Lithium as we cook using induction and have a small water heater.
This is where the meltdown has started, it appears my auxiliary setup is used to power the trailer lighting and sensing, I have 2 extra cables going to the pos terminal, I have one red and a red/yellow that splits in to 2 cables, and then I have the the 10mm positive. I have read loads about how to fit a B2B but a lot of it says the cables to the battery and earth under the seat need to be upgraded, but If I connect the pos and neg to the Victron XS 50amp it will leave those other cables without power.
I'm assuming another way around it, is to leave the under seat battery and come off of that to the XS, but I have read conflicting reports about that also requiring cable upgraded, I could use the original auxiliary to power just the LED lighting.
All the wiring from the XS would be in 16mm.
Any help would be greatly appreciated.
