i just tightend them up pretty tight by hand, no speciffic torque, just keep the two bolts equal. the best way to get the dp out is to get the car as high up in the air as possible, take the 2 bolts off the turbo elbow, then take the 4 bolts off the back of the cat, if you can get the front two holding the cat to the dp off, take them off and take the cat off, i bet it will be rusted on though. then just wiggle it and twist it out. but the turbo stays right where it is, unless you want a ton of extra work.
the key is getting the car as high as possible, if you have access to a lift use it, it will save you a ton of headaches.