working 12 hours a day.
Oh dear ... not one of those high school math things ...
let's see ...
per day earnings: (8 x 25) + (4 x 37.50) = A
per month earnings based on 22 day work month: 22 x A = B
annual: 12 x B = C
Next ... what the tax rate on annual income C? ... =D
Subtract: C-D, divide by 52 ... and that should give some sort of weekly ballpark figure.
I think you'd fall into a 40% tax bracket ... which means you'll be taking home about $210 a day although you'll be making $350 a day. If you only work 6 months, and relax for six months, you'll get most of it back.
Take home per month will be between 4 and 5k.