Hi there,
My name is AD also from Thailand, Pun asked me to visit and join this site. I don't know if I can post pictures as I'm new to this but will try.
First of all, let me say something about Opel (yours is Vauxhall) Omega situation here in Thailand. Omega's had been imported since Omega A came out. The first Omega B was introduced in 1995 (1994 model) and had been marketed here until around 1998, most were sedan(saloon) with 2.0 version. Very few MV6's were imported. If I'm not mistaken, only 50 Wagons were imported through those years, also in 2.0 version. Mine is a wagon. We have 2 clubs here for Opel, first one is
www.opellove.com (established 7 years ago) the other is
www.opel.in.th (2 years old). You can visit both sites but maybe you will not be able to see pictures unless you register in.
As Omega is more than 10 years old, parts are expensive. And yet, engine has too many sensors that need replacements very often. So, quite a few owners, including myself, have their engine changed to a Toyota engine code JZ. There are 2JZ (3.0) and 1JZ (2.5) to choose from, both come with either turbo or non-turbo. 2JZ seems to work perfectly with 3.9 ratio final drive (originally in 2.0 Omega). No problem with availability of the engine as there are a lot used engines from Japan. No problem also with wiring and electronic thing. Thai people are keen with this, it's an easy task.
Once you change the engine, front discs and shocks need to be replaced with those from MV6. Used parts are available importing from abroad. Now, you can use your Omega trouble-free with this modification. According to our law, we can not import used cars (CBU), unless you are a Thai citizen staying and owning that car abroad for more than 18 months and would like to bring the car back when you return. That's all I wanted to say at the moment. Will try to post pictures after this.