Say I start a new game, what's the quickest way I can complete the MQ using the console?

Journal, C3-DestroyDagoth, 50
But that could possibly break other things in the game, and most of the game will definitely not act as though you've accomplished the entire MQ. You also will not earn any rewards or benefits that you gather along the way doing the MQ.

If you wanted to use all the console commands necessary to fully reflect the MQ being completed, you will have to search through the UESP Wiki or the CS to find all the relevant Journal and Dialog entries to add, and scripts to run. Have fun with that

If you are just looking for a way to get it done quickly, a mod would be easier. http://mw.modhistory.com/download-18-7219

Thanks, I just want the ghostgate gone. See thread..

http://www.gamesas.com/topic/1509315-ghostfence-removed-mod-problem/

Finishing the main quest just removes the magical fence, not the tower structures.
You'll have to make your own mod to do that.

Since your questions here have been answered, you can use your other thread.