The top bit was probably transferred from another page of notes where I explored possible altered scales, but I didn't dig through the notebooks to find it.
I assume this is literally the piece of paper I stared at while recording the backing track. (It's possible it's a later recopying, though, but I doubt it. It could have been recopied before I recorded it, though, given the lack of changes. There's probably another page with the altered scale notes laid out on a guitar neck for me to look at while I improvised--probably in the notebooks which I didn't dig into.)
And in fact I can see from that that I wrote this in 1987; the recording is dated 1989 because that's when it was released on a demo tape for friends. So, yeah, the 20 year anniversary of this is sometime around now.