im currently in the process of swapping out my wilwood big brake front setup back to stock calipers n rotors. Should i drain all the fluid out of the oem calipers? Also should i just remove the brake line from the wilwoods without bleeding it?

 

No, don't drain all you brake fluid. Try to keep as much brake fluid as you can, cap off the tip so none comes out. The more fluid comes out, the more you're going to have to bleed your brakes after you're done.