Not to question anyone's stats or intent, but here's a listing of GEN-FOUR CAMARO
components, throughout the car:
Driver's 6-way Power Leather Seat = 42 lb.
Passanger's non-powered seat = 34lb.
Passanger Air Bag = 17 lb. (includes bracket)
Driver's Air Bag = 10 lb. (which is likely the weight of the seat bags)
So, removing TWO 6-way Seats (from a Gen-5) that contain TWO Air Bags is gonna total a bit over 100 total, imho. Add back the weight of the replacements (and their tracks/adjusters/adaptors), and you have a net weight loss of (maybe) 50-70 lb... One-piece seats will weigh less, but offer NO recline adjustment beyond fore-aft. Two-piece aftermarket seats, with adjustable seatbacks, will diminish the weight savings further. And typical aftermarket seats are NOT air bag-equipped.
Notice the difference in weight between non-powered and powered seats...6.9 lb/ea, so 1LS seats would save 14 lb (with Air Bags) over 1SS seats, while maintaining OE safety standards for street driving.
Notice deleting the rear seats (29 lb) and belts/retractors (5 lb) = less than ONE front seat...
Notice the A/C compressor and condensor, and Power Windows/Locks/Keyless weigh a total of 32 lb...which pops the "urban myth" that Gen-4 1LE F-cars weighed a LOT less...they didn't!