Hi Rick,
I'm not sure that there is any difference between silver steel and drill rod, either way the only time that I heat up silver steel is when I am making a tool that I want hardened so that it will cut BMS or black bar. The threads on mine were cut without any preparation other than turning to size and using cutting compound.
The attributes of "Silver Steel, Drill Rod and Gauge Plate" are that as you buy them they are soft, ie machinable, ground accurately to size and able to be hardened by heating to a specific temperature, often described as "Cherry Red or Bright Red" and then quenched in oil or water. You can buy grades of these steels that are intended to be water quenched and those that are intended to be oil quenched. It usually specifies on the package wrapper exactly what temperature you should heat up to, to obtain a specific hardness and how long and at what temperature to anneal at.
I have only used these steels because I happened to have them to hand. You could equally well use anything convenient to you, particularly if you have a scrapyard or engineering works accessible.
I hope that you are going to take some photos of your work. It would be nice to see them.