Thanks for the replies, which has increased my confidence that this is a job I should be able to handle!

One thing, you refer to "cutting the thick cable connecting the two batteries". As I want to fit a voltage sensing relay, can I simply fix the relay to either side of the cut cable (plus the ...

I have a "winter pack" Bongo with twin SBs. I want to convert to a single SB with a separate LB circuit. Question is what circuits do I need to route to the LB? I think that I once saw a description on the Forum of a simple change to just or two wires, but can't find it now I need it!)