Since I'm going to have to do this in the spring for the E-test, I thought I'd have a look at mine:
Here is a photo:
Its hard to believe, but those are probably supposed to be four nuts/bolts holding the Catconverter (left) to the exhaust tail bracket (right) welded to the trailing exhaust pipe.
The probable reason for this arrangement is simple. Heating up the Cat Converter with a welding torch probably damages it.
So the cat converter comes pre-welded to the front-pipe, which is bolted to the exhaust manifold coming from the engine (there will be some kind of asbestos sealing ring too). Then the rear of the Cat Converter is bolted to the plate (shown rusted out here) that has been previously welded to the rest of the exhaust system.
Thus, if you order a cat converter for this system, an arrangement like the following is probably easiest:
Get one with the manifold pipe attached. prewelded, and the plate on the rear.
They have one for $106 here:
http://cpwstore.carpartswholesale.co...294967219+2268
You can see from the picture that you just need to unscrew the bolts at each end and replace them afterward.
You want to try to avoid welding if possible, so as not to damage your new converter.