Also works in the nether!

The schematic has the quarry and the synchronizer (i call it) in it. I suggest you make 2 schematics from this. You only need 1 synchronizer. You can make multiple variants of the quarry by changing the redstone links (just replace the items in the links, you need 1 item/quarry, there is 6 total on the quarry).

After that you can just put the quarrys next to eachother, and if your computer can handle more than 6 you can expand the syncronizer by putting more links on it. If you aling the drills with a chunks it will perfectly mine out all the other chunks.

If you rotate it West or South, change the rotation on the up most rotation speed controllers.

Unloaders/storage not inculded.

Altough the quarrys theoretically can go on forever, they stop after moving out the simulated render distance, to run the quarry i suggest you make a seat and a little box on the last quarry.