mm that's a tricky one , well lets think about the distortion a bit,the creamy top end makes me look at a fuzz, maybe an octa/fuzz with the octaver low in the mix, cause i hear some low end which i cant really explain otherwise (but that does not refer to the core of the sound).
So , yea, Fuzz would be my go to effect in that situation (it's not a very high gain fuzz , more like gilmourish fuzz). But before you steer to other effects test and try a lot of fuzz, octafuzz!
Fuzz plays tricks with your mind in this one , cause if done correctly , you can both hear a good mix of the clean sound (that's why you think it's an unplugged guitar) and the distorted one, it's like the 2 sounds co-exist nothing like normal distortion or overdrive , which change the sound 100%. That said , of course it could be a piezo mic'ed guitar (like those acoustics that they play).
Every time you think about bands and sounds in recordings , allways think about the context , i can see it happening before my eyes , the guitarist going "hey man let's run that acoustic through my fuzz and laugh" if you hear a band experimenting a lot (like radiohead) it's a bit harder to understand some sounds, but if you hear a more typical band (in terms of experimentation) then the whole thing is a bit narrowed down by itself.
So recap, definately check out acoustic guitar through fuzz, also i think there was a bit of hybrid playing both pick and fingers in some notes.
Now to quickly explain the rest of the sound, i think the acoustic/fuzzed guitar is recorded via DI in the tape machine (cause i hear minimal space) --That's also a classic practice with acoustic guitars to avoid weird feedbacks.-- now this one is panned Hard Left!
Then there's a delay (used as pre-delay) panned Hard right! 30-50 ms (50 is a bit stretched for this vibe) that goes to a reverb.
This way you can create that kind of effect where the guitarist plays on your left , and on your right there's a big wall that echoes and reverbs the whole playing (also amplifies it a bit so check your stuff with compression to make the sound a bit fuller, giving the perception of loudness)
Last , EQ accordingly, use the Tone knob of the fuzz until the sound is kinda dull but the top end is creamy , if no avail use the guitar tone to feed a dull(-er/-ish) signal to the fuzz (which sometimes decides that every sound passing through it ,should be brighter than the original :P ).