I sent an email today to expedition essentials asking if they could or would make some similar for the 4th Gen. This was their response.
Chad,
We would love to come up with something; if you have contacts who are 4th gen owners that may live in the Bellingham WA area we would need to locate a volunteer for a few days of prototyping and test fit.
If anyone lives near there and is interested please message me back so I can make coordinations, and hopefully us 4th Gen owners can an awesome mount. Please see the link below if you are unsure what the T4RPAM is.
Toyota 4Runner Dash Mount Powered Accessory 5th gen 4runner - Expedition Essentials