Flashing updated uboot in Manjaro

[TDC_PBP]

Does anyone have clear, specific instructions on how to install the updated uboot in manjaro? I tried to follow these instructions in the /boot file in manjaro:
flash_uboot() {
  echo "A new U-Boot version needs to be flashed onto your install drive. Please use lsblk to determine your drive, before proceeding."
    echo "You can do this by running:"
    echo "# dd if=/boot/idbloader.img of=/dev/mmcblkX seek=64 conv=notrunc"
    echo "# dd if=/boot/u-boot.itb of=/dev/mmcblkX seek=16384 conv=notrunc"
}

## arg 1:  the new package version
post_install() {
  flash_uboot
}

## arg 1:  the new package version
## arg 2:  the old package version
post_upgrade() {
  flash_uboot
}
but....the second dd command failed (never gave any visible output) and I temporarily bricked my PBP . I don't particularly want to repeat that experience EVER again, so I don't want to try it again until someone else gives it a good look over. Confusingly, I found these instructions printed in the terminal while doing pacman -Syyu:

(213/215) upgrading uboot-pinebookpro                [############################] 100%
warning: /boot/boot.scr installed as /boot/boot.scr.pacnew
warning: /boot/boot.txt installed as /boot/boot.txt.pacnew
A new U-Boot version needs to be flashed onto /dev/mmcblkX.
You can do this later by running:
# dd if=/boot/idbloader.img of=/dev/mmcblkX seek=64 conv=notrunc
# dd if=/boot/uboot.img of=/dev/mmcblkX seek=16384 conv=notrunc
# dd if=/boot/trust.img of=/dev/mmcblkX seek=24576 conv=notrunc
(214/215) upgrading xorg-server-common       

Thoughts/ideas??
P.S. I am running Manjaro from my emmc and did check to make sure I flashed the correct drive (the emmc)