It should all be good then roebuck. And that clears up the mystery - I thought I remembered that tank well enough to know if it had a lump there.

Does your carburetor have an automatic choke? It looks to me as if it does. If so you have to preload the diaphragm when you reattach the carburetor to the tank, with the diaphragm in between. First though, check that the top of the tank is flat, by laying a reliable straight-edge across it diagonally. You can see the instructions here:
[Linked Image]
[Linked Image]
[Linked Image]

Please report back here as you go.