Yes you'll get a little more power but you'll also have more harmful emissions. An EGR Delete on an N/A engine really doesn't make much sense to me. A lot of guys block off their EGR's on L67 engines but that's only because they are supercharged and any reduction in intake temps make a big difference. If you do it and don't remove the codes from the PCM then yes your check engine light will be on and I'm pretty sure that the PCM will pull timing to protect the engine so any power gains will be negated. On the other hand, it's probably one of the cheapest mods you can do (just fab a block off plate or even weld a penny in the hole) and you're done. I would also assume that anyone with a Tech-II should be able to disable the code. Good luck if you decide to do it, and let us know if you see any gains.