Sunbird Help

I have a 1994 Pontiac Sunbird with about 123,000 on the OD, I bought the car for $200 and 20,000 miles ago, recently the cat went, (kept ratteling around), Took off the old cat, and it was all broken off inside (ok no big deal), borrowed a car and got a new cat and what not. Installed it, the car now runs really rough, and when I got out of the car after a 1 mile drive I smelled like burning wires or rotten eggs or something, well I look under the car, the brand new cat was BRIGHT RED. Could the new cat be shot or could the car be on it way to the grave yard, please help!!!!!!

Definately clogged. Hell, maybe even on backwards. Long story short, the air isnt getting out of the cat.

No air out of the engine, no air in...car will run like crap, mileage will plummet, the exhaust fumes will back out (causing the rotten egg smell) and the exhaust system will glow bright red up to the blockage...

get rid of the cat altogether, i say. and for 200 bucks, that's a decent find if the car works well.