About two hours. Ensure to be home alone, sell pets and children.
Be well-rested. Work methodically. Take a break when needed.
Whatever you put the Gyro on, make sure it is sturdy so it won't
bow/warp under the Gyro's weight, stable, does not wobble at all,
and utterly and completely level.
Build the Gyro layer by layer, and check that they are all ... level.
Michell Orbe/SME IV/Lyra Delos/Michell Iso & Orca & Alecto Stereo/Quad ESL-63/Denon DVD-2930/Apogee MiniDAC/Pioneer N-50 streamer