100% not the cdi, if the cdi is not working then you will have no spark, this is a old sled, are you sure it is cdi and not points?
Check that you have spark, if yes then check compression, and also pull the exhaust off, take a light and look up at the pistons to see if there is damage
If you don't have spark, and you have a new coil, then your wire or cap could be no good
If it is a points ignition that can be your problem as well
Let me know the answers and we will go from there
Fix it till its broke!