Well, the build schedule was definitely pushed back more than I would have liked, but here's the status update (pictures will come later):
Left/right upper/lower arms/legs are fully glued, as is the belt. The chestpiece is only missing the final edge pieces, which will be glued on this evening.
The upper leg/arm pieces & belt are able to slide on as-is for fitting verification, but the lower leg/arm pieces are too narrow to slide on (as indicated by null.exe in his original thread), but I expect them to fit. I also very carefully tried on the chestpiece Sunday night and it fit perfectly.
Today I should be starting the resin/fiberglass process. Being one to procrastinate, I am now scrambling to find tutorials on how to best do this step... Needless to say, this is getting down to the wire, and I don't truly expect to make the Halloween deadline. If I manage to finish the resin/fiberglass/bondo/painting process by Friday, I may be able to purchase and assemble the undersuit Saturday and still make it, but we'll see what happens.