SAB,
Welcome here you are on the right track.
With the revving problem and the air filter off you can see the governor arm on the end of the spring and if you push the arm to the left it will decrease the revs, if you stretch the spring slightly you will see that the revs drop so you can work around that point. Did you get it started using the primer and if you did then leave the carby alone it is working fine. If you start it up and run it several times there is a good chance the smoke will clear, the problem it quite often happens
