Here is my console output when I installed the upstream Linux kernel header and image .deb files, on Ubuntu 14.04.4.

I will still be rebooting my system after this to see if the install worked. Just thought I'd provide this in case it helps.

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nicholas@Nicholas:~/Downloads/Linux Kernel Test/v4.7-rc3-yakkety$ sudo dpkg -i *.deb
Selecting previously unselected package linux-headers-4.7.0-040700rc3.
(Reading database ... 259391 files and directories currently installed.)
Preparing to unpack linux-headers-4.7.0-040700rc3_4.7.0-040700rc3.201606121131_all.deb ...
Unpacking linux-headers-4.7.0-040700rc3 (4.7.0-040700rc3.201606121131) ...
Selecting previously unselected package linux-headers-4.7.0-040700rc3-generic.
Preparing to unpack linux-headers-4.7.0-040700rc3-generic_4.7.0-040700rc3.201606121131_amd64.deb ...
Unpacking linux-headers-4.7.0-040700rc3-generic (4.7.0-040700rc3.201606121131) ...
Selecting previously unselected package linux-image-4.7.0-040700rc3-generic.
Preparing to unpack linux-image-4.7.0-040700rc3-generic_4.7.0-040700rc3.201606121131_amd64.deb ...
Done.
Unpacking linux-image-4.7.0-040700rc3-generic (4.7.0-040700rc3.201606121131) ...
Setting up linux-headers-4.7.0-040700rc3 (4.7.0-040700rc3.201606121131) ...
Setting up linux-headers-4.7.0-040700rc3-generic (4.7.0-040700rc3.201606121131) ...
Examining /etc/kernel/header_postinst.d.
run-parts: executing /etc/kernel/header_postinst.d/dkms 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
Error! Bad return status for module build on kernel: 4.7.0-040700rc3-generic (x86_64)
Consult /var/lib/dkms/bbswitch/0.7/build/make.log for more information.
Setting up linux-image-4.7.0-040700rc3-generic (4.7.0-040700rc3.201606121131) ...
Running depmod.
update-initramfs: deferring update (hook will be called later)
Examining /etc/kernel/postinst.d.
run-parts: executing /etc/kernel/postinst.d/apt-auto-removal 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
run-parts: executing /etc/kernel/postinst.d/dkms 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
ERROR: Cannot create report: [Errno 17] File exists: '/var/crash/bbswitch-dkms.0.crash'
Error! Bad return status for module build on kernel: 4.7.0-040700rc3-generic (x86_64)
Consult /var/lib/dkms/bbswitch/0.7/build/make.log for more information.
run-parts: executing /etc/kernel/postinst.d/initramfs-tools 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
update-initramfs: Generating /boot/initrd.img-4.7.0-040700rc3-generic
run-parts: executing /etc/kernel/postinst.d/pm-utils 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
run-parts: executing /etc/kernel/postinst.d/update-notifier 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
run-parts: executing /etc/kernel/postinst.d/zz-update-grub 4.7.0-040700rc3-generic /boot/vmlinuz-4.7.0-040700rc3-generic
Generating grub configuration file ...
Warning: Setting GRUB_TIMEOUT to a non-zero value when GRUB_HIDDEN_TIMEOUT is set is no longer supported.
Found linux image: /boot/vmlinuz-4.7.0-040700rc3-generic
Found initrd image: /boot/initrd.img-4.7.0-040700rc3-generic
Found linux image: /boot/vmlinuz-3.13.0-88-generic
Found initrd image: /boot/initrd.img-3.13.0-88-generic
Found linux image: /boot/vmlinuz-3.13.0-87-generic
Found initrd image: /boot/initrd.img-3.13.0-87-generic
Found linux image: /boot/vmlinuz-3.13.0-86-generic
Found initrd image: /boot/initrd.img-3.13.0-86-generic
Found linux image: /boot/vmlinuz-3.13.0-32-generic
Found initrd image: /boot/initrd.img-3.13.0-32-generic
Found memtest86+ image: /boot/memtest86+.elf
Found memtest86+ image: /boot/memtest86+.bin
done
nicholas@Nicholas:~/Downloads/Linux Kernel Test/v4.7-rc3-yakkety$ 

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