Roger, after two new lucas type alternators failed I fitted a Brise. Fit and forget! Like you I'm not electric savvy, what I did on my Vitesse was tuck away the Brown/Green cable (not necessary on the Brise) and connected the Brown/Yellow to I believe the L terminal (someone please say if its the S!) I then ran a new cable (that's the green on the photo) from the alternator IGN to a switched ignition white on my fuse box. Connect the large charge cable alternator to battery and hey ho it works! The ignition light functions and it charges!
I'm not sure if the green cable is the correct size and my terminals are not insulated, apart from some tape, but it's been fine for the last two years and 1000 miles.
I hope this helps one electrical novice to another.
Iain