I’ve put together a Pinterest board with all sorts of useful info, images and ideas pinned up to help with Hauptwerk building:

Hauptwerk AGO Organ Project: General sites

CONSOLE ideas: Ideas for DIY organ consoles

Building the console: parts, materials for console building and where to get them

building the bench: I ended up buying my bench, but if you do decide to build one yourself…

MIDIfying Pedalboard + Manuals: getting a pedalboard and manuals midi ready.

Sound System for your Hauptwerk