There's more weight savings in removing the excess bumper crap, than anywhere else on a 77 Camaro!
The other place to save a fair amount of weight, and gain performance is aftermarket aluminum heads. That's a big money item, so you need to decide how serious you are about weight loss to spend the money for good heads.
Lighter wheels can help, but it's unpsrung weight, and not as helpful as eliminating sprung weight.
You can also relocate weight and make a difference. Take that heavy battery from the front and put it in the trunk where the weight will help, not hinder.
I've added weight to my Camaro vs. stock weight, and not gone slower. Usually weight loss wont make as big a difference as HP gains. When I built my '71 I was drag racing, so I added subframe connectors, traction bars, and a rollbar. Big weight items, but needed for strength and safety. At the same time I was adding performance items on the engine, so my times were going down as the weight went up. I've always felt the time and money going towards performance mods was better spent than most weight savings mods.