[walrus01]

In a modern tightly integrated vehicle, taking apart the dash enough to remove the whole integrated head-unit is a real pain in the ass. If you can buy a unit for $200 on ebay and test it on a bench, the author probably considers that to be a good use of their time, nevermind the plastic fasteners.

If I were to try to take apart the dash of my car I'd guess I would be looking at a 6 hour project minimum.

[londons_explore]

Not only that - if the project takes 6 months, your day-to-day car ends up without a head unit for that long...