1993 Buick Lesabre Rattling Noise

Sorry I hope it's not too much to ask but you could you briefly describe where exactly are the bolts and the catalytic shield located? If possible can you please include a picture? I tried to look for pictures online but Im still clueless. I just don't like taking it to a mechanic cause I always get ripped off.

Thank you so much you were right on the money! I checked the catalytic converter shield first. Sure enough one of the rivets was missing and when I moved the sheets of metal around it made the rattling sound. Thanks again. However, I was wondering what you thought of this other problem I have. Not all the time, but sometimes, the car will accelerate on its own. If I let go of the brakes, it will start speeding up. And once Im about to park, when I shift it into park, it will sound even louder, like if Im flooring the gas pedal. Someone told me that one of the vacuum lines connected to the throttle body could be damaged. I checked and a few of the rubber unions were very cracked, so I replaced them. But it's still doing it. What do you think?

Hello and sorry to bother again. I was going to clean the Throttle body but when I took off the big plastic pipe that runs from the air box to the Throttle body I noticed there's a thin metal screen covering the entrance to the throttle body. I did some research on it, and some people say that it's better to take the metal screen off because it allows more air to flow into the engine, even though its there to allow the air to flow in straight and to block any piece of debris that might get past the air filter. But what do you think? Would it make any major difference to remove the screen? Thanks.