Being a 97, does it have the 02 sensor behind the cat? If not, you won't need the simulator. I thought it was 98 when they started to use them. You want to make sure and keep the 1st one there without a simulator as it controls your air/fuel ratio.
To answer your question, I run a simulator on my 98 Dodge. It has worked flawless for about 2 years now. I got it at o2simulator.com . It basically just tells the computer that there is a cat and its working fine.