I should have expanded my EGR exploding story. The reason it exploded was because the two pre-catalytic converter exhaust manifolds started shedding their guts and clogged up the main catalytic converter and caused back pressure strong enough to explode the EGR. The clogging will greatly decrease mileage. The main cat can be removed and tapped against the ground to get those pieces to come out. When pointed toward the sun like a telescope, you should be able to see some daylight. If it is too clogged, it has to be replaced.