The Beatles Rock Band

This achievement is an accumulated score of your high scores on Bass for each song.

This can be done on any difficulty

For this, I started The Beatles story on Guitar on Hard.
Once I had received the Gear Guitarist achievement I switched to playing Bass and played the rest of the story with the Bass

As there are no achievements for completing the story with any instrument I thought this would be the best and easiest way to kill two birds with one stone.

The score of 1,000.000 is accumulated in either QuickPlay or Story mode. It is for the highest score you get on each song. So there's no point in playing the same song over and over again.

This can be on any difficulty, obviously the higher it is, the quicker it'll go. Quickplay counts just as well as story mode. It only counts your best score per song, though, so playing the same song multiple times won't help you. However, you must play the songs solo. If you play with someone else, it won't count.

This can be on any difficulty, obviously the higher it is, the quicker it'll go. Quickplay counts just as well as story mode. It only counts your best score per song, though, so playing the same song multiple times won't help you. However, you must play the songs solo. If you play with someone else, it won't count.