Welcome to the forum.
As for your question of making a custom case for a laptop....I would personally pull off the screen and use the laptop like that. I've pulled many laptops apart and they are rather delicate outside of their specific case. Plus Wranglers haven't exactly been known for the smoothest ride...so keeping the orig case would make it a bit more durable if mounted properly.
In case you are wondering I run a modded laptop as well.