Sounds good! Be sure to keep us all updated on your project!
One thing though, it might not really be a problem, but just telling you.
The ITPS will not survive cranking and in a lot of cases it will require you to have the engine running to be able to operate your PC. For some people this might be problem...
If you want to use your PC when your engine is not running look into one of the Opus solutions - the Opus 90W will probably be more suited for you. Or if you already have an 12V DC-DC powersupply you might look into the Carnetix PSU.