I'm with MockTurtle on this one; "250k pots are what you should being using." The 500k pots are typically used with the Bartollini actives.
Also, be sure that you soldered the cap. to end terminal, and the other end grounded to the tone pot. A .05 cap it standard issue, but you can go as low as .02 for less treble cut as you trim the tone pot down.
michael s.
BTW: if you're looking for parts and wiring configs, check out
http://www.guitarelectronics.com for parts and wiring diagrams