They shouldn't be too bad unless the car is a rust bucket. You will need some big tools and some good leverage -- and I like to use a small propane torch to heat the bolts up and loosen any rust up -- you can use penetrating oil as well.
Thei dea is pretty basic, you take off the sway bar and it's four bolts. Be sure you have a couple jackstands to put the car on (supported by subframe) and a jack to support the axle so you can raise or lower it to help with lining up the bolts and taking tension off of everything.
Yes, you can do both at the same time. Yes, you can reuse the stock hardware.