stupid Tripod sites..anyone else checkin' that out may have to copy/paste shortcut into browser. I tried to fix that but I can't turn off Tripods silly link problems.
Anyway, yes the wing was a first gen option on the ES cars. In fact, to my knowledge there were two options for them. One looks like mine, the other sits much lower, and is quite a bit wider (and the tips are attached to the quarter-panels) so essentially choice #2 is a 3-piece wing.
Pimped's right, those are my tails, check out the how-to sections.