Although I now provided a few Truck editions suitable for 2GB devices, it might be time to hand the work over to everyone that needs the map faster or with other modificatios.
Since the procedure is pretty straight forward I will just sum it up in a few easy steps.

Before you start:
Make sure you have the complete Truck map and of course that a meta code is available.
You also need a full featured country map from within the coverage of the Truck map - either the country you mostly drive or just something small like the DACH map.

How to make the map small enough:
Firstly be aware that all these mods will cause some negative effects too, like no POI's, different visibility of park and industrial area and other minor things.
All that won't affect the pure Truck navigation though...
Ok let's get going, shall we?
1. If not done unpack the downloaded maps into corresponding folders on your hard drive.
2. Create another folder to store the smaller Truck map in.
(of course you could just extract what you need, but simply copy and delete is easier for most users)
3. Copy all files from the original Truck map into the new folder - your working folder from now on.
4. in the working folder delete all cspeech files as well as the following files:
crpoi.dat
poi.dat
cphoneme.dat
5. from your single country map copy the following filesinto the working folder:
borders.dat
citymap.dat
citymap.met
faces.dat
faces.met
Confirm to overwrite existing files!

If you still have enough room left you can add the crpoi.dat and poi.dat files from the single country map to get POI's of your area,
add the csspeech file for your language,
or simply add some music
Be aware that especially the 32mb devices will need some free MB on the storage to perform properly!
If you fill up until you only have less than 10mb left you most likely will get into trouble during navigation.
Since this is all a last resort option I would advise to just leave it with the above and not to use spoken street names of the whole POI collection, after all it will also reduce the performance on low end devices.

Important notice:
Tests showed that the latest Truck map that can be slimmed down for 2GB devices is the 945 edition.
All maps after that are simply too big in size to be stored and used with a Navcore on the device.
If you need a newer map version you need to consider soldering in a SD card or to upgrade your device to one with a SD slot.
The Go x20 and x30 models are prefered here.