Where are drivers installed on the Mac

Hardware Drivers in OS X are typically in the form of Kernel Extensions and the primary location is /System/Library/Extensions/ however they can also be within an Application Bundle. You can use kextunload to unload a Kernel extension. To see what Kernel extensions are loaded use the kextstat command in a Terminal.

Have a look at the manual page KEXTUNLOAD(8) and also the Unloading a Kernel Extension with kextunload section in How to Load & Unload Kernel Extensions in OS X, excerpt show below.

Unloading a Kernel Extension with kextunload

Unloading a kernel extension from OS X is basically the exact same as loading a kext, except you’ll use the kextunload utility with sudo as follows:

sudo kextunload -b com.apple.driver.ExampleBundle

Or by pointing directly to the kernel extensions path:

sudo kextunload /System/Library/Extensions/ThirdPartyMystery.kext

Again, you can confirm the kernel extension has been unloaded by using kextstat and grep, where it should return nothing.