vehicles VS computers
Someone's wish is customers can assemble their own vehicles like computers. Tough it is crazy, you can find the similarities between vehicles and computers.
1) cpu vs engine Both of them are the key component to drive the whole systems.
2) motherboard vs vehicle chassis Both of them are the host for other devices.
3) northbridge vs transmission Both of them are the nexus between the key component and the other devices.
4) Computer chassis vs vehicle iron shell. Both of them are the outside parts.
5) cpu fan vs engine fan Both of them cool the key component.
I think the biggest gap for the end users to DIY their vehicle is, the devices in vehicle are analogous and the system will not be guaranteed to function well after all the necessities are plugged. It depends on the experience of the end user to make the vehicle as better as it can be. That is, you can DIY a vehicle with all the necessities and it can run in the road, but the gasoline consumption may make you mad.