If you get fuel out of the line at the carb... the filter wouldn't be the problem. THe only way the filter would hurt then is when your romping on it and it can flow enough to kep up with the carb/motor demand.
Spark plugs... a real easy way to check to see if the coil is firing... just use a spare plug... put it on the wire, place the grounding tip to the head and crank. Look for spark.... if you can't tell for sure... do it in the garage with the door shut... but it should be obvious.
If your concern is the spark plug wires... you can pull the wire at the coil, leaving the spark plug in the motor and hooked up and crank... see if it arcs from the coil to the wire.
While looking at the EHC, turn the key on... no lights should be present. Then push RUN, one light should come on. ***This being your EHC is somewhat current***
Then, check your thunderheart ignition. When you crank you should get lights flashing on your ignition module. I'm not sure but I bet yours looks a bit different. But I think they still hv lights on it...
For the one above, the red light to the left would come on when you push RUN and the EHC sends power to it. The other 2 lights are one for each cylinder fire that the unit sends to the coil.
Also, maybe check to see if there is a reset button on your coil. Some do.
Further, check your crank sensor as well.
Oh, and you're not starting it with the throttle open are you?