LostArt nailed it - The Gibson Maestro FZ-1A would have been the fuzz pedal most likely used in the US in 1966, in fact it was all but ubiquitous on almost any garage/punk/psych record that had fuzz. I found this post I did from a few years ago with more info on that, the FZ-1 came first but wasn't used near as much as the FZ-1A. Minor differences but worth noting.
there's a particular bass sound that the bb's used from good vibrations on... that fuzzy buzzy distorted sound (carl apes it on long promised road, etc) and i would love to know what the method was on getting that. just plain overdrive? playing through a guitar amp? a specific pedal?
Given the time (1966-67) and the place (Los Angeles), if the sound is what you also hear on Fire and Cabinessence from the Smile sessions in '66, I'm pretty sure that's a Gibson Maestro FZ-1 or FZ-1A fuzz pedal. They first started appearing more around '63, there are actually photos of one near George Harrison during a She Loves You session at Abbey Road where they reportedly attempted to use it on the song but scrapped the idea. It's the fuzz pedal that you most likely hear on 9 out of 10 psychedelic and garage records from 65-67, the best example to my ears being "Incense And Peppermints" from Strawberry Alarm Clock where Ed King (later of Skynrd) used his Telecaster through an FZ-1A into a tube amp for that classic tone. That to me is *the* ultimate fuzz guitar tone, and perhaps to other players as well since several pedal makers have done clones of that exact sound in pedals like the "Peppermint Fuzz". Keith Richards *also* used the Maestro pedal on Satisfaction, even though the time and place might have suggested he would have used a Vox or other pedal more specific to the UK guitarists (among them Jimmy Page still doing sessions with the fuzz tone as his calling card), but Keith's choice was also the FZ-1A (or FZ-1, basically the same except to purists and collectors).
Keep in mind too, there were some custom built fuzz boxes out there too, one that comes to mind is McCartney's tone on Think For Yourself. It's been said that was a box built for him, others have said it was just one of the Vox pedals, etc. Just search some of the Beatle gear sites, they'll have every possibility dissected. Same with Hendrix, he was using pedals custom built by Roger Mayer like the "Fuzz Face". I have one of those, it does have a different character and a different way of breaking up the tone and trailing off than the FZ-1 boxes which you can actually hear if you know what to listen for.
But chances are, unless specifically mentioned by the original player, if you hear a fuzz tone on a record cut in 1966 or 1967, especially in the US, chances are they were using the Gibson FZ boxes. They were ubiquitous to some degree at that time.
There just were not that many pedal effects available in the 60's, you had a choice of either fuzz or wah (after Clapton cut Tales Of Brave Ulysses and of course Hendrix with his Mayer custom effects like the Octavia on Purple Haze), and that was basically it unless it was a homebrew. The "top boost" wasn't as much a pedal as it was a device you'd connect between guitar and amp, and the boost would drive the amp to create tube distortion, a different wave form and sound than "fuzz". Other famous overdrives of this kind would be created in the studio, as Emerick did with Lennon's voice on Walrus and his guitar on Revolution - They'd deliberately overload the tube preamps going into the board.
The other effects were tremolo/vibrato, most of those came from the effect circuit on the old amps, although there were standalone units, some of them pretty far out in design (including one where the sound would literally be routed through a can of oil...and it turned out the oil in that can would turn toxic and be dangerous if the can leaked).
Steel guitar players in the 50's created the boo-wah effect by turning their tone knob, which was basically a manual wah-wah. Chet Atkins claimed he had made what could be the first wah-wah pedal, where he could do the boo-wah steel sound with his foot, but says someone stole that one-off from a studio where he had it. Then Vox came out with the Clyde McCoy wah in the 60's, and Clapton and Hendrix ran with it in 66-67. Everyone had to get one after that.
So that was about it for pedals in the 60's, with some exceptions.
Into the 70's, perhaps the most heard new addition would have been the MXR Phase 90 and its variants. It seemed like every track at some points in the 70's had a guitar or keyboard through a Phase 90, including I believe some BB's tracks from that era.