crankshaft VS PiShrink

But, according to : https://github.com/opencardev/crankshaft/wiki/Android-Auto-Wifi

It's pi focused apparently https://github.com/opencardev/crankshaft/wiki

3)The route that I ended up going was to build my own unit with a Raspberry Pi running Crankshaft to run Android Auto and a 7" touchscreen that I mounted magnetically to a phone mount that inserts in the CD player. Doesn't look OEM butif you manage cords it looks pretty clean and works well. Also cost me under $100 and I can remove it easily any time I want. I'm a little techy so it wasn't too hard - there are tons of videos out there that will walk you through the project.

How about this? https://getcrankshaft.com/

Your other option, which I actually use in my R56, is to utilize the Crankshaft project with a Raspberry Pi and a generic 7" touchscreen from Amazon. I mounted mine with a magnetic mount from the CD drive and power it through the aux power port. Mine works both with wired and wireless Android auto, with very few glitches. If you're techy at all it doesn't take long to set up.

There is a small utility, which shrinks the image by omitting the empty space. Then you can write it to any SD card, which the data will fit on. So in your case even on a 2GB card.

backup.sh - this is what makes the image and uses pishrink to shrink it

Depending on what single board computer you are using, you may want to look at PiShrink. This will at least allow you retroactively shrink the image you create to the actual amount of space used.

I was pretty familiar with most of this but I did not know about the "image backup" utility. You may also want to look at PiShrink in your process as well.

I run a full dd to create an image and then run pishrink https://github.com/Drewsif/PiShrink on it. I used to manually size the partition down with gparted and calculate how much to dd and then gparted the new card to expand the partition - too much work. Pishrink does all the work for you and is fast.