i have a 97 360 and i hollowed out the cat, but im not throwing a check engine light, i know its a good thing but shouldn't it be on?

 

Some do, some don't. It's not a definite.

 

Does the CEL come on when you first turn the key to the ON position (before you get to START)? They all come on for a few seconds (self-test type of thing). If yours doesn't, your CEL bulb is disconnected/burned out/taped over.

However, if it comes on for the self-test, it could be that your truck runs cleanly enough that the sensor can't tell the cat is gone.