Good to hear from you - I know the name from the discography on the web - good work!
I presume the 12" you have is the one displayed at http://members.aol.com/fujikikun/kanren.html
? If so, then I think that the Massey mix only appeared on the white label, and not commercially, but I could be wrong... Graham?
I'm still collecting a mass of 808/Massey mixes at the moment, with the latest being the wonderful Heitor mix, and the Yes 'Owner Of A Lonely Heart' mixes - wonderful!