I reccomend using two hydrokinetic engines chained together, with an automated canola farm outputting to a decent number of grinders. (I'd say 16-32, though that would probably be overkill if you don't plan on making more) Use a shaft junction to split the power of the two, with one of the engines powering all the grinders and the other half constantly powering a multi-directional clutch. Set up this clutch so that when you have one lever on, it outputs into a bunch of gearboxes that transforms into 512nm torque, (First stage requirement) another that transforms into 256nm torque, (Fourth stage requirement) and a third that transforms to 1nm torque. (Second and third stage requirement, along with water)
This requires some thinking and a bit of learning, but really sounds much more daunting then it is. Just remember that you need the redstone trail to be going into the multi-directional clutch, which is something that tripped me up a few times before I figured out what was happening. And once you have this set up, it requires no switching gearboxes or really any manual input at all, other then occasionally flipping a lever or two and feeding the machine ore.
It will be slow, however. So very, very slow.
Once you have bedrock, you'll be able to upgrade your power net more easily. I recommend magnetostatics, and whatever energy generation method for RF of your choice, but spamming more hydrokinetics works too. Or maybe a gas turbine with an ECM.
Also, for powering an extractor at maximum one-tick processing speeds, you need 16MW for the first stage, 1MW for the second and third, and 8MW for the fourth.