Advices for G Project

 Hello everyone, 

I'm not exactly sure If I should post my topic in "Buying Advice" or "G Mods" so I'll just stick with buying advice. This is my very first post and I have just registered to your lovely forum so hi! 

I'm graduating from university (finally) and have decided to take on one of my dream projects (transforming a G-class). Basically my goal and ambition is to buy an old G-class (460 according to Wikipedia) and transform it into a daily driver that suits my taste. So change the body to a more modern look with custom bodykits and change the interior as well. Overall the dream is to build a G-class that is what I actually want and looks good at a franction of the price of the newer beautiful G-classes. However my knowledge about the G-class is pretty limited so I was wondering if you lovely folks could help me out. 

I'm Turkish and thanks to our beautiful tax laws cars are pretty expensive compare to other European countries. On top of that there are only handful of G-classes for sale and are very limited. 

The options within my budget are: 230, 240GD, 250GD, 280GE and 300D. Since the price of fuel is very expensive in Turkey I was hoping for a gasoline engine and add LPG to it. The bodykits would be a replica from aftermarket manufacturers (I found people who are willing to let me borrow them so I could replicate them; perhaps in fiberglass) and the interior console would be custom built adding in one of those smart touchscreen navigation/audio player devices. In the end from the outside it would be a Hamann Typhoon looking truck with a custom interior. Of course this is a project/dream so I'm not even sure if it is possible. 

My main concern was about the engine and transmission. I do not know how to drive manuel and I would like to stick with automatic transmission. The cheapest G-class I found is about 15,000 pounds while there are plenty of manuels for 7,500-10,000 pounds. Would it possible to transform a manuel transmission into an automatic ? Would it have to be a G-class transmission or could I get a transmission from another car (e.g. something that is popular in Turkey so it would cost much less?) or should I just stick with an original transmission?

Also which of the engines would be more suitable for daily use (no off-roading) and easier to maintain? Please keep in mind that LPG is a must. 

Again another question I have is regarding the engine. Would most of you prefer the engine the G-class comes with or would it be sensible to swap the engine? I've heard a lot of people putting 2.0 V6 Subaru engines in lightweight custom fiberglass chassis (400-700kgs) replicas and apparantly they are very fast. 

Could the steering wheel be swapped with a ML-class steering wheel? 

These were the questions I had in mind and would be great if you could input your views & opinions. 

Thanks!