What is this exhaust smell in my car?

After some unparticular amount of driving at pretty much any speed, once I come to a stop, this nice exhaust fume wafts into the cabin. It is very pungent and irritating. I feel for fellow motorists around me. But I’m not sure if it is a rotten-eggs smell or just a plain exhaust smell. It is definitely the byproduct of combustion and not just raw gasoline.

If I won a million bucks for guessing the right answer right now, I’d say it’s the exhaust manifold crossover. On each of the 5000 or so TGPs that have been made, the crossover is highly prone to leaking. Can you give me an idea of what to check for on the crossover to indicate that it is leaking?

If you’re someone who responded on my question about exhaust work, know that I haven’t done anything yet and will probably invest my money on things that actually need repairing, such as this.