[Fiddlebog]

if you kill the fuel pump and just spray starter fluid in, you should get ignition. If not, it's definitely not a fuel issue.
Is there any way the ignition timing could be off? I worked on an old carb-engine a while back, and the magnet for the hall sensor had gotten out of alignment causing the ignition to be out of phase. Don't know enough about the CPS in these engines to make any conclusions, though.