Nope. Back in the 80's GM used to sell a kit for everything but the G-Body. I can recall reading a TSB or something like it and the reason was that the G-Body didn't need them. It was safe enough. I dont know if that was real fact or just some BS as back than the G-Body was going to be canned in a few years. They made a kit for the B-Body and later they were standard on the 88-90 so I'm thinking BS. A quick trip through the boneyard turns up several platforms that didn't use rear shoulder belts until around 1990 too. For example the A-Body and J-car.
