I asked Quadratec whether the trail rail floor tracks fit the 4xe -- they aren't sure at this point but they believe a 4xe specific version will be released soon.
Picking up my 4xe high altitude in a couple of hours.
Ordered - 5/22
Build sheet - 6/8
Window sticker - 6/10
Shipped - 6/14
Delivered to dealer & picked up - 6/21