Hi
As per current layout Volume 1 is shown as going to Ground. When 9v Battery was connected it worked but when connected to 9v Power Supply I got a loud Thump, Thump, Thump. I linked Volume 1 to + side 10UF Electro Cap when I retraced rocket88 trace circuit
http://guitar-fx-layouts.42897.x6.nabble.com/Top-Gear-Fuzz-Sustain-td31845i20.html and as he noted that Volume 1 is not grounded and it is linked to Boost 1&2 not 2&3, Boost 1 changed to Boost 3 as builders have recently found that Boost was reversed.
Hope this Helps future Builders
Cheers!