theory is lousy,but, it IS finger picked with the odd 2 or 3 note chord formed while you're doing the old

----5-7
---5---
--5---6
-7-----

etc,.

According to Ye Olde Tab Book ..the chords are (apparently)

"~Am~ ~C+addB/G#~ ~C/G~ ~D/F#~ ~Fma7~ ~G~ ~Am~" times 2,

then "~C~ ~D~ ~Fma7~ ~Am~ ~C~ ~G~ ~D~" times 2.

This is repeated until just before "Oooh it makes me wonder" when the main chord sequence comes in.

Bon Chance.