You'll probably need a stock wrench to loosen the castle nut on the buffer tube. Watch the buffer retainer when you begin to unscrew the tube, it has a spring under it. Watch for the take-down spring and detent as you remove the buffer aswell.
The mag release is simple, just push it in real far and you can unscrew it from the other side. Hold the button in hard and watch you don't scrape the surface on the other side while you unscrew it. Watch for the spring under the button.
Bolt catch and trigger guard require a punch to remove as already stated. I wasn't able to get these out on a DPMS lower I had and sold the stripped lower with these parts still in. I hope you have better luck. The bolt catch has a small spring, watch for it.
For the pivot pin I have found using a dental pic tool helps to push the detent in with the pin pushed only slightly in, then when you have the detent pushed in you can rotate the pivot pin so the detent will no longer engage. This is where you need to be careful as it will want to shoot out when you completely remove the pivot pin.
To get at the safety use a long screwdriver to remove the grip. There is a spring held in place by the grip that will come out, along with a detent that pops the safety in each position. You may need to remove the trigger to pull out the safety, I forget.
Trigger & hammer should be obvious, push the pins out, carefully, starting with the hammer.
