Oh, RiverNut. I now feel like such a bane. Please PM me your address. I have one surviving oring (used but in tact) on the pin, which is presently out of commission anyway until I can get that other part. So please let me send you mine. I'm one short anyway and have to order an oring set.
Thank you so much for answering this.

I tore my original insulator all to heck trying to get it out to replace the brass connector a few months ago and the insulator I ordered was too long. This one is shorter. Thank you tremendously.
RE: where the orings go
When I replaced the brass connector before, I just left the orings on (and close to the threaded movable piece on the pin...I can take a picture if you want to see) and screwed the pin into the insulator. I'm assuming the orings ended up in the right place because the tension on the pin was perfect. When I unscrewed it to put the steel connector on, they had been inside the insulator, so I think, in the process of screwing the pin into the insulator, they automagically get where they're supposed to go? Anyway, I would not consider this pro advice so maybe someone else can be more helpful. Had to share my experience with it, though.
It is also shown this way (pin > threaded part > orings > insulator) at
GGTS User Manual - E-Cigarette Wiki(Diagram 2).