A lot of the Sonics sound was acheived by pushing the amps and red-lining the mixing desk I believe. That Outsiders track (and most of the fuzz sounds on the BFTG series) is almost certainly a Gibson Maestro Fuzz-Tone (probably an FZ-1A), judging both by the sound and the year ('66). The Seeds used a Maestro fuzz-tone. The Mosrite fuzzrite is a really fantastic fuzz but is more along the lines of Dave Allan and the Arrows, the Ventures and of course Iron Butterfly. The Ashbass clone is a pretty good and great value clone but I reckon the Mahoney fuzzrite clone, Jerms, DAM stuff is better, although it will cost more. The Boss FZ-5 maestro patch is to an original maestro as a mobile phone photograph of a Van Gogh is to the original painting, imo. It will give you a flavour of the maestro and the way it changes your approach to playing but has some ugly background digital artefacts, gates absolutely and abrubtly (unlike an original) and has no depth of character to the sound - a 2D rendering of a sculpture perhaps?! As far as FZ-1/FZ-1A clones go, the best I have heard use the original transistors and that would really be Jerms or Creepyfingers. Ghost effects makes a very good FZ-1 clone using non-original transistors and is consequently much cheaper. A Big Muff was really a late 60s/early 70s fuzz after Hendrix convinced the guitarists of the world that they needed loads of wailing sustain and I don't personally feel it will get you anywhere close to the tones you are describing. The best resource regarding the early fuzzboxes that I have found would be the DAM forum, frightening amount of knowledge held within those pages!
Conclusion? Maestro Fuzz-Tone FZ-1A or FZ-1. Good luck with your quest anyways!
