Yes, you are correct in your deductions.
If it is an early 2000's model, it is going to be the 155 HP model.
To access the fuel filter you will need to remove the seat then look towards the front of the cut out for the engine compartment. Just underneath that edge you will see the fuel filter/water separator.
Here is a parts diagram that shows what the filter looks like, it is #7 in the diagram.
You may need to use a screwdriver to carefully pry the fuel lines off the filter. Try to do this without shaking the filter too much. If it gets shook up and it had water in it, it will temporarily mix with the gas. If you suspect it did get shaken up in the removal process, just let it sit for about 15 minutes undisturbed then carefully pick it up and look for water in the bottom of the filter. Water will appear to look like air bubbles laying on the bottom because the water is heavier than the gas and will sink once it separates again.
Remember when testing for spark, make sure that the spark plugs are away from the open spark plug holes in the cylinder head. If they are close to the spark plug holes it will ignite the fuel and cause a ball of fire. With a reasonable level of caution, this is not a dangerous test. Follow my suggestions and you will be fine.
If you have any more questions or are unsure of exactly what my suggestions are or what they mean, please stop and ask me. Your safety and satisfaction are of paramount importance to me.