I am new to the chicken world, and recently installed a nipple drinking system.
A few things I learned:
You need a 11/32" drill bit to install them. It is kind of a hard size to find on its own, but they are in almost every drill index. You may have to borrow the bit from someone if you don't have that size.
When you screw the nipple into your drilled hole, you need to use teflon tape. Every one of mine leaked w/o it. I had to take them all apart, teflon tape them and reinstall. Problem resolved.
If you put them in PVC, make sure you drill your holes in a perfect line, and MAKE SURE they hang down as perpendicular as you can get them. I had one that was at a bit of an angle and it tended to drip quite a bit
You'll have to train them to drink out of them. I left my bucket in the run for a few days after installing mine. I would sit outside with a stick and hit the waterers to make them drip. It took about 4 afternoons for them to figure it out. Now I have no more crap/dirt filled buckets.