You say you're getting spark on a "dry" plug, yet you think it's flooding? If you are indeed getting spark and the plug is dry, try dumping a teaspoon of your premix into the spark plug hole, screwing the plug back in and giving it a few kicks. If it tries to run (burning off the introduced fuel), but then stalls and refuses to run again then you know you've got a fuel delivery problem and we can work from there!
Big thing is to ensure you are indeed STILL getting spark on the plug. Also, does it feel like you've at least got the same compression as the engine had prior to the rebuild? (Just to ensure that you've got compression within the engine--we'll worry about a solid number later if necessary)
I did notice that you've tried starting fluid. If the plug is dry though, you should get the engine to at least "stumble" with some type of fuel in the chamber. Another idea, if you've DEFINITELY got spark and the plug is wet when you pull it out of the head, you may try "bump" starting it. Those '80s should bump start pretty easy.