I can say that since I install about 5 kits per week. I can say that the tools needed are: drill with hole cutters for handle and lock set, square for good perfect 90 degree angles, shims, long screws to attach to frame, and if handy a recipocal saw to cut through the nails when the molding is removed, you will also need a good pry bar.
What ever you do, you must be square regardless of the squareness of the rough opening. The shims will allow you to make the kit square by adding shims here and less there.
Do not overtighten the screws fastening the kit to the rough opening studs. This will bow the kit in and make the closure not proper. Using screws allows you to make in and out adjustments. So, nails, in my opinion are not recommended.