Steve, I did not read, or do not remember your previous post so I am going to make you a step by step as I would do it, and you make the calls from there. I agree with the belting a fresh tractor, with another operator if at all possible. Cranking a big tractor that already has hard starting problems makes life crappy.
1. Take your air cleaner lower box off until you get it running. I just finished an la that had enough stuff in the air intake to fill a pickup truck.
2. Remove #1 plug, check that your impulse is tripping when the piston is all the way up and heading over center with a zip tie in the hole, AND that it is the compression stroke.
3. Are your wires wired the correct DIRECTION OF ROTATION? I do this for a living and still have done it wrong more than I care to share.
4. Have you checked spark as suggested? The auto store spark tester will not cut it. For future projects go to an echo dealer and tell him you would like to order one of his inline spark testers like he uses in the shop. It is adjustable, has a clear window for the spark and will allow operation while it is installed.
5. If you have all these things in order where you feel good about them, belt that sucker up and let it run on the belt a while. I am going to get dogged about this, but if you still aint getting anything, use some carburetor cleaner in where your carb draws from the oil box and see if it will fire. The tractor will run on it and it is no more harmful than a bottle of gas, just easier to manage.
If you don"t get it, repost and ill give you my cell if you would like.