Base/NISMO Seat with integrated SRS airbag = 42.4 lbs
Airbag assembly from SRS Seat = 1.6 lbs
NISMO Cat-back 'H' Pipe [Midpipe] = 17.2 lbs
NISMO Cat-back Rear Muffler Section [Can] = 35.2 lbs
NISMO Cat-back Front 'Y' Pipe [bolts to cats] = 13.6 lbs
Base/NISMO Headunit/Radio = 2.6 lbs
Rear Under bumper Charcoal Filter Cover/Shield = 0.4 lbs
Charcoal filter is kinda a wild card, but I had to take it off to make room for my passenger muffler can from GTM, Here's a picture
And here is the NISMO CAT-back that I weighed
Rear muffler section, Midpipe or H pipe, and Y pipe that bolts to the cats.