Can't remember them all now, but, in essence you are right, the extra wiring is for stuff on more upmarket models!
The reds are for illuminating the gearshift quadrant on automatic cars, (live when sidelights are on) so are "spare" on 90% of Dolomites and there will probably be an earth for the same thing.
Others may have to do with seat belt warning/handbrake warning and other similar minor tasks.
Steve
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey, Now with RWD and Carledo powertrain!
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