So far, I've actually found no way to change the default controls for the turning signals. I would like to get them working on my wheel buttons since I have some extra ones un-binded
Bring up the profiler screen and make sure you've select LFS.
Run your mouse over the right side selections to find what button they go to.
When you find the one you want to map, left click and select command/new command
Give it a name.
Press record and press and release the key you want to assign (8 or 9 for turn signals if I remember correctly.)
Click ok.
Back on the main screen click on the same button again and instead of creating a new command, select the one you just created. The name you gave it will show up in the box.
You can even assigne one button as the "Shift" button and get a whole set of other shifted buttons to use. I do this for my pit arrow keys, they are the shifted directional buttons that I normally use for the look functions.
This is more easy than it seems.
First of all, set 4 binds: "/press 7","/press 8","/press 9","/press 0".
Then assign each bind a button on the controller.
Now have fun