plug
 

OEM = original equipment manufacturer.

I know that, but thank you.

iridium are the OEM for this car. My question is, what is people opinion of them, and the other questions I've had

As close as I can tell, iridium spark plugs are a variation of platnium. Have long life and cost more. I personally see no reason why they will not work in any engine no matter what country it came from or any ignition system no matter what type it is.
The serve the purpose of plugging the hole where spark plugs screw into the head and carry the electicity to make the spark.
As does any other type of plug.
The material used will last longer than say a plug using Porcelain as an insulator and lesser metals as an electrode.
As to doing something else other than just lasting longer, I would attribute all additional claims to supposed performace increases to that of advertising hype!

To answer your question about how to change the spark plugs mozzer, that rectangular panel on top is what you need to remove to get to the plugs. But before that, you need to remove the bracket for the throttle cable. (I can provide pictures if you need) Then just lift on the rectangular "ecotech" panel until it comes off. (not a ton of force just keep pulling and wiggling little by little. If it flys up it may hurt the throttle cable.) Then just set the panel to the back. The plug wires are built into the panel so you dont need to worry about them getting out of order. Replace your plugs (Iridium only please) then put the panel back, tighten it down, and put the throttle cable bracket back on.

I just replaced my 03' ION's plugs at 66k just a little while ago, they say 5 years or 100k miles is when they need to be replaced, so i did it since its been 6 years. They weren't damaged (just a little nasty) and I didn't notice any immense performance increases, but it feels good to keep a car in top shape. :)

Ok after all of that you do not need to replace the plugs in an ecotec for 100,000 miles. If for any reason you have that area of the engine apart and have 75K on the plugs go ahead and swap them out.

Torque on your 03
 

what torque did you yse for the 03’

L61 Ecotec - Overview, Torque, Fluid, and Engine Specs - Performance Forum - j-body.org - The J-Body Organization

Every torque spec, capacity, fluid spec you'll ever need for a 2.2 L61

15ft lb -- use the low end of a 0-50 or 0-70 ish ft lb wrench; the lower values for any wrench with 0 --- (whatever) will not be accurate at the low end

And please do no reply to 9-year-old posts