Drilling the hole turned out to be very easy, The wafers are hard and drill easily. I always use a block of wood to back up the wafer because occasionally they will break while drilling and you will get to hold a spinning bit with your bare fingers.
I use solid core bell wire to hang the algae wafers. Just tie a not in one end of the wire, slide on the wafers and hang it where the snails can't get it. the wire is stiff enough that it can be bent about any shape you need. In the aquarium I hang it over the side and close the lid. The aquarium top is heavy enough to hold it in place and holds the wafer a few inches from the side. My fish are crazy about algae wafers and put on a good show when fed this way.
The wafers will stay on the wire a surprisingly long time.
Here are some of my red blonde guppies and some sunburst platies attacking a wafer. The video isn't that great. It looks good on my end but gets messed up when youTube processes it.
Here are my red blonde guppies in my out door stock tank feeding on an algae wafer.