Yeah I'm thinking the same thing, probably carry over equipment to streamline componentsI would love to know that myself.
Or to get a look at the wire connectors at the front door speakers and or behind the head unit.
If anyone is working on their factory stereo please post pictures!!
My gut tells me that the base audio system will be similar to the base Tundra and therefore aftermarket 3rd gen Tundra non JBL components could be used in 4g Tacoma but I cannot confirm that assumption as of yet.