These are the tutorials I used:
Needed to change the RaspiBlitz script to install the Bitcoin Core 0.16.3 instead of the now unavailable 17.0-RC3.
For the HDD I used this X820 expnsion board http://www.raspberrypiwiki.com/index.php/X820.
This way only one power source is needed and will be nice and compact once housed without the LCD on.
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