oh, you didn't say that. i thought you were referring to the solo. i doubt the lead guitars in the intro and chorus were actually played by jeff. anyway - yes, it's harmonised. bear in mind that you can't just play the phrase in different parts of the neck. it's a little more complicated than that, because you have to stay in key, which means adjusting the intervals in the phrase to fit. some theory knowledge is required.
for a quick fix, try placing the intelligent harmoniser after the cab block. set the key to Eb ionian. set the intervals to 3 and -4.
this may not sound exactly like the recording (i haven't got the time or the inclination to work out exactly what's going on, sorry), because harmonising in strict thirds and fourths can lead to some notes which aren't desirable (i.e. don't land on chord tones at the end end of phrases). when multitracking this kind of stuff, it's usual to adjust the harmonies slightly, so they don't exactly follow the melody. (as a teenager in the 80's i was slightly obsessed with recording harmony parts on melodies and in solos, so i bumped into this problem quite a few times). maybe some kind soul can help you out with a custom scale to really nail it.