dual battery ?

the previous owner set up his dual battery using a redarc smart switch and i can't be bothered going through all of his wiring to change it over to my ctek 250 as there are way too many bloody cables for me to figure out, so will just keep it as it is..

but my question is - it seems he has ran 6 or 8 gauge (american) cable right to the re and wired that up directly to two baintech cigi sockets - i'm replacing that with my old baintech powerboard as it has everything i need but i'm not going to be able to get both cables through the entry point in the unit due to their size - can i use 30cm of smaller cable that i already have connected in the unit and attach it to the larger cables?

if so is it a case of crimping and off you go or do i need to attach a circut breaker or fuse?

Without knowing cable size and current draw its impossible to know

Should be ok but I would install a fuse at each end and the fuse must be one that protects the smallest cable size. That is to say that the cable the previous owner has installed might be say 20 amp capacity. If you connect onto that with a cable rated at 10 amps, then your fuse must be 10amps or less.
A fuse at the load end protects the baintech powerboard, and the fuse at the battery end protects you from fire if the cable somehow shorts out to earth, and protects the battery itself.

Ok - it's a 6AWG cable running from a 95AH deep cycle down the passenger side to the cargo area. The guy had this directly connected to the baintech x2 cigi sockets.

My old baintech power board still has the same cable that I attached to my 105AH battery with a 40AMP auto reset circuit breaker. So I'm thinking that I can attach the positive to a 40AMP auto reset circuit breaker and connect the other side to the 6AWG cable that runs of the 95AH battery..

This sounding correct?

Think I'm gonna get flustered again..

Ok - it's a 6AWG cable running from a 95AH deep cycle down the passenger side to the cargo area. The guy had this directly connected to the baintech x2 cigi sockets.
I would have had fuses or breakers protecting that but if they weren't there well they weren't there.
My old baintech power board still has the same cable that I attached to my 105AH battery with a 40AMP auto reset circuit breaker. So I'm thinking that I can attach the positive to a 40AMP auto reset circuit breaker and connect the other side to the 6AWG cable that runs of the 95AH battery.
If that is what you had before it should be ok. The baintech will be protected by the 40amp breaker.
the only extra I would do is put a 40Amp or so breaker/fuse where the 6AWG cable connects to the battery. This would reduce the chance of fire in a major crash or roll over. Sorry mate not trying to be funny. I just don't like the idea of having a rollover and a cable doing a slow meltdown and starting a fire before I could get out or be helped out. maybe I'm a bit paranoid.

rolly is my middle name!

;)

ok just need to locate the cable going to the rear and will snip it at the battery and re wire with auto resets unless PO installed one

Just a thought on those cig outlets , throw them in the bin they will fail, especially now you'll be driving dirt roads a lot.
Search and find the Baintech rear merit and volt gauge that fits in the rear cut out on the passenger side.

ah im not using those cigi plugs - i got my old powerboard that is usb, engel and merit with an volt meter in it so will just attach that..