The wire of the cap soldered to the contact of the pot has ASBSOLUTELY NO contact to the housing of the tone pot?
If there is any contact between one of the pot contacts and the (grounded) housing, the tone pot will work as a master volume! The cap has to be between Ground (housing) and the contact of the pot (and via middle contact of the pot to HOT) without any other contact.
The SD drawing is right for people who know what they are doig (and why!).
Download my 5.5 MB 360 page "wiring bible" (in German) and go to 1.1.21 (page 23 at the moment). You will find the 100% same wiring but with a "better" cap illustration. The schematic (light blue background) also shows you why the tone pot works like a master volume when the cap is bridged ... http://161589.homepagemodules.de/t29...-E-Baesse.html