There are some mass changes to do to some Alfa Romeo models in my opinion:

1983-86 Alfa Romeo 33: correct model name should be Alfa Romeo Alfa 33
1985-87 Alfa Romeo 75: correct model name should be Alfa Romeo Alfa 75
Alfa Romeo 90: correct model name should be Alfa Romeo Alfa 90

Sorry if I posted this in single comments but I didn't know there was this thread on the forum to be used.

Fiat Uno chassis codes:
[146] should be for European 1a serie (1983-89)
[146A] for European 2a serie and Innocenti Mille Clip (1989-ownwards)
[146E] for Brazilian MkI Uno/Fiat Mille/Innocenti Mille (a different car than the EU ones, with Fiat 147 chassis: model origin should be Brazil)
[146B] for Duna/Premio/Elba/Penny

2001-2003 Aurora is GMX160
2000-2005 Bonneville is GMX310
2000-2005 Buick LeSabre is GMX220
2000-2005 Cadillac Deville is GMX270
1995-1999 Buick Riv is G-Body
1997-2005 Park Avenue is 97PA.
1998-2004 Seville is S5S.

That GMX690 is the whole generation.

Ah, thanks for clearing that up!

Fiat Punto:

I believe GT and HGT models (and maybe even Sporting) should be written in model name

For all "Iveco-Magirus EuroCargo", model is "EuroFire".
http://www.imcdb.org/vehicles_make-Iveco-Magirus_model-EuroCargo.html
http://www.imcdb.org/vehicles_make-Iveco-Magirus_model-EuroFire.html

What do you mean by that?
Is it better to use that one to have a common code? Or the specific ones?
"G-Body" does not sound much like an official code.

The inclusion of "Alfa" in the model name or not was previously debated, so for that I would wait the opinion of other members. We already changed previously these.

What criteria shall I use to know which ones are the European ones?

All South-American built ones are Brazilian origin. The exterior differences are a different hood clamshell and the fuel cap on the left side. Other Unos are Italian models.

There are some models which in my opinion should be set as origin EU, because they were designed in Europe mainly for EU-market:

Hyundai i20 (all series)
Hyundai i30 (all series)
Hyundai ix20
Kia cee'd (all series)
Kia Venga
Nissan Micra [K14]
Nissan Qashqai [J11]
Nissan Terrano II/Ford Maverick
Toyota Auris Touring Sports [E180]
Toyota Corolla Verso [AR10] and Verso [AR20]

Hyundai i10 (both generations) should be origin India in my opinion

1988-2000 Fiat Tipo: chassis code is [160] where missing

European Ford models:

according to Wikipedia (but I have often read this also elsewhere) currently A- and B-segment cars are developed by Ford UK together with LCVs.
So wouldn't it be opportune to set models as Fiesta, Ka, Fusion (EU), B-Max and Transit as origin UK?

I mean what criteria shall I put in my query for the update.

I noticed that we have Dodge Aspen Wagons listed as their own model, but not their Plymouth Volare wagon twins. Change?

The 1993-2002 Nissan Quest and the 1993-2002 Mercury Villager use the chassis code VX54.
https://en.wikipedia.org/wiki/Ford_VX54_platform

The 2001-12 Ford Escape, 2005-11 Mercury Mariner and the 2001-11 Mazda Tribute chassis code is [U204]

That's weird.. was there a difference in naming between Dodge and Plymouth ? if not i don't see why..

Which one is the right one between the two names styles?

We already have V40/V41 for the Nissan in these year range, we would loose the difference between these two codes