The cable you have floating in your lower picture is main positive alternator output usually labelled as B+ on alternator. It should be the thickest one and brown/white in colour. It goes to load side of ammeter with other brown/white wires. The battery side of ammeter has plain brown wires one of which goes to battery via the common connection point of starter solenoid.
If in doubt just remember the battery feeds start system and maybe horn directly and loads (ignition, lights and hazard) via ammeter. If you're unsure of ammeter connections it doesn't matter if you get them the wrong way around as long as all brown go to one side and all brown/white to the other, it will simply work in reverse with regard to charge/discharge.
Smaller brown/yellow wire goes from I or AL connection on alternator to charge warning light of course fed by ignition so it comes on before engine is started. Presence of (3w) bulb is important as it provides initial field current to kick-start alternator once engine running.
Hope this makes sense.
BTW the top picture shows alternator output connected directly to battery so it could not possibly show charge current into battery on centre zero ammeter.
Thank you - yes I've come to the conclusion that my car is wired correctly and the wiring diagram on Gomog is incorrect.
When I first had her I swapped the alternator bulb for an LED in error. The correct 3W went back in!
