I did my best to document the build in the videos and the project logs.

Acquire a PB7220 along with an extra chassis an oversized lid and some end plates you don't mind modifying. Also acquire a SBC, a hard drive and a copy of Windows. Yes, it has to be windows because that is all the software works under.

Modify the extra chassis and lid as detailed in the drawings. You can used a Dremel to modify the endplate and allow a VGA connector and extra USBs

Further modify the lid and mount the THz Optics cubes to it. The cubes come with the PB7220 and can easily be attached to the lid. The steel frame members keep the optics basically aligned.

Make the short cable that will connect from the power port on the bottom of the PB7220 motherboard and power the SBC and hardrive.

Transfer all the components into the modified chassis and attach the SBC and hardrive to the lid. Connect the SBC and hard drive to the power cable that you made and then connect that to PB7220 motherboard.

Attach the peripherals to the SBC and turn the PB7220 on. This should power up the SBC. When it boots for the first time, install windows and then install the PB7220 control software.

Attach the endplates and the lid. Attach the THz source and detector heads to their THz optics cubes that are attached to the lid. Connect the electrical and optical cables to the heads.

Attach the feet and the mounting bracket to the PB7220. The feet will allow you to set the unit down without bumping the THz heads. Technically, this is upside down, but it doesn't really matter.

Slap some cool stickers all over the system and tape up holes that may allow dirt and rocks to enter the unit.