Thanks for your comments, Romer--I'm glad you enjoyed the recording.
As for who did what: I played the acoustic guitar, which is mostly just there for texture, and four electric guitar parts including the 12-string in the opening figure, the rhythm figure that plays through the main body of the song, the guitar behind the first half of the second verse, and the arpeggios in the chorus. Paul plays bass throughout; his first guitar part appears under the second half of the second verse. He then plays all guitars in the bridge (except for the acoustic, which is barely audible but still there providing a bit of texture) and all lead lines through the end of the song (not counting the 12-string as a lead line--that's me). There's also a synth pad I played that just fills out the sound a bit--it's played throughout the song except in the bridge. All drums and percussion are computer-generated, I'm afraid. Paul actually dabbles with drums, but he doesn't own a set, and while he has access to a set through his bandmate, they don't really have the setup necessary to record drums well. And of course neither one of us owns an optigan. As for the vocals, I did the Neil parts for the most part (there's one bit in the chorus where Neil and Tim briefly cross over, whereas Paul and I stay on the high and low parts respectively), while Paul did the Tim parts.
In terms of process, I did a full recording of the song myself, playing all instruments, then stripped out a lot and sent the remaining tracks off to Paul (leaving my harmony vocal intact so that he could use it to learn the part). Paul then recorded his parts in Thailand and sent the whole thing back to me. When I first received it and listened to what he'd done, I found myself cursing--he'd forgotten to record his vocals! He'd just left my harmonies in place! The fool! Except that there was one bit where I could have sworn I'd sung it a bit differently...and of course it turned out that he had done his vocal after all; it's just that his "harmony voice" sounds exactly (and I do mean *exactly*) like mine. It was downright spooky.
Anyway, Paul had an interesting take on the song--he likes the Finns' music, from Split Enz forward, but he's not a fanatic by any means, and he hadn't spent hours trying to pick out all of the nuances of the Finn Brothers' recording, as I had. He brought some things to the song that I hadn't expected. So after absorbing what he'd done, I then went back and rerecorded a couple of my instrumental bits, added a new guitar track to the chorus, did one or two small "producery" things (moving bits from place to place, that kind of thing), and spent about two weeks mixing until I had something I liked. Both of us worked in Garageband on Macs, so exchanging and working with each other's files was easy, except that they were too big to move over the internet (my favorite conversation during the whole process was with a FedEx employee, who told me that they could get a DVD-R from Indianapolis to Chiang Mai in 36 hours for $58, but then helpfully added that if I wanted to save some money, they could do it in five days for $57. I paid the extra dollar). Garageband is a hobbyist app and very easy to use, but it has large chunks of Logic Pro/Logic Express code at its heart, so it's capable of producing some very good recordings in skilled hands (not saying that mine are). I think that this recording pushed the program to its limits--there are something like 25 separate tracks, although I don't think there are ever more than ten or twelve going at a time--but somehow it all worked.
As for the forthcoming Coop Brothers album, well, it's much-discussed, but we're both so busy (and my songwriting proceeds at such a slow pace) that it'll probably be a decade or so. But someday!