Jake, this did the trick! I was still not able to simply replace the EFI/Clover folder with the bootpack files and config, but through trial and error I finally came to a point where the boot completes and everything is working.
Dell Latitude E5550
macOS Sierra 10.12.6
Working:
Intel HD 5500 Graphics w/QE - tested internal display, HDMI output, all working (did not test VGA)
Charge/battery/sleep/wake - all working, including power management functionality
Audio - tested internal speakers, HDMI output, all working (didn't test headphone jack)
Bluetooth - tested iPhone hotspot, working (but throughput slower than iMac)
Webcam - tested with FaceTime
SD card reader - tested with SDXC
Wifi - current card will never work so I will either buy a USB wifi or find an internal replacement card (not sure if that would work)
I will work on the keyboard setup later so I can get hotkeys working (volume already works). I notice that there is no brightness slider in the Displays preference pane. I'm assuming brightness is controlled by the keyboard only?
Overall, this setup is very fluid. Booting takes longer than a real MacBook, but once boot completes then the performance is very equivalent to a real Mac.
Jake, I really appreciate your assistance, and all the work you have put into developing and maintaining the bootpack files. Let me know if there is anything I can do for you (further testing, etc).
Thanks again!