The 1.6 in the EL is not quite the same as the 1.6 in my '99 SiR, but those photos sure look familiar, and that sure looks like the cat that lives under my car.
AFAIK, there's only one cat on all of the 1.6 litre B-series engines, and it lives downstream of the exhaust header, underneath and slightly behind the engine block.
As far as heat shields go, I know that they are used to keep grass and other stuff under the car from igniting, but I also seem to recall that they are placed around catalytic converters to help keep the heat in. Since cats need high heat to operate properly, wouldn't the shield also help the cat warm up faster, and help to retain heat when idling or operating under light loads?
Dunno for sure, but you might want to think twice before cutting it off.