You want the holes to be as accurate as possible, since any leaks mean a loss of efficiency in your still. The reflux tower is made from a 14 inch piece of 1 inch copper tubing. A piece of 14 or 12 gauge copper wire is soldered across the pot end so that the marbles cannot escape into the pot. Unless you place the wire so you can push it through the hole in the pot lid, make sure that you solder the pipe to the lid first. Be careful when wrapping the small copper tubing around the top of the reflux tower - it has a strong tendency to kink.
Microwave cooking thermometers work quite well.
The garden hose will go onto the pipe connectors much more easily if you heat the end of the hose with a hair dryer before attempting to attach the hose. It is best to use silver solder when making these connections - the alcohol and acid mixture is quite corrosive to metal. Using silver solder will prevent lead from leaching into the distillate. The Process Operating the still is quite easy, however there are some things that you should be aware of. There is a tendency for the pot to boil over, so don't fill it up too much unless you like to clean your stove a lot.