When you open the hood, you will see metal color piece of metal sitting on the top of the engine, that is plenum.
The plenum is what the air flows through going into the engine. Instake manifold is another name for it.
The Eclipse was released on 03/26/2010.
if your eclipse is a 6 cyl then it is on the back of the intake plenum and it is easy to get to as you have more than enough room to room it with just a socket and small rachet.
I got quoted $500 on my 00' eclipse gt
Assuming it's the V6, there are 3 in the front and 3 in the back under the plenum. the 3 in the front are really easy to get to. a good walk through on removing the plenum is here: http://home.pacbell.net/fong8/gstuff/tjc_plenum.htm
You can remove the spark plugs in your 2003 Mitsubishi Eclipse by turning the spark plugs to the left. You should use a 5/8 deep well socket. The spark plugs will come out.
YesYes
6.5 in front 6x9 in rear
bank 1 sensor and bank2 located under air intake (plenum) on top valley of 03 6.0l 364 gas Chevy engine.
I think it's 60K.
Starter is located underneath plenum.
I don't much about cars. SORRY!!!!!!!! Bootscootn-00-04 eclipses' have the same parts. What you can do is search online for part numbers for an eclipse. If the 03 eclipse part number matches the 00 part number then there will be no issues. I have bastardized my 00 eclipse with several different pieces.