What is a sii file and how do I open a sii file?
An SII is a data file used by 18 Wheels of Steel: Haulin', a truck driving game. It contains properties for a truck, such as the engine class. These files are saved in plain text format and may be altered to create custom truck configurations. SII files can also contain a list of referenced truck files for the game.
Relevant sii file links:How to open sii file on Youtube
How to open sii file on Wikipedia
How to open sii file on Microsoft.com