I have no idea whether the adapter will work or not.
However, the idea of PCI cards and adapters in a vehicle installation does not sit well with me.
The normal vibrations and bumps of everyday driving can easily cause a PCI or PCI-E card to work loose. That can cause all sorts of problems with the PC, up to and including frying equipment.
If you are dead-set on using a PCI or PCI-E sound card, make sure that is is 100% securely installed and has almost zero chance to work loose.
Easier said than done.