Heater control valve for A/C truck really needed?

[mcspeed.1]

I tore into the dash of my truck tonight to see just how bad it had been cobbled up over the last 43 years. I must say that I am rather impressed as to how many original parts are still in place. However, there are no vacuum lines attached to anything! As you can guess nothing was working either! I removed the entire heater box inside to get to all the mode doors as they did not seem to be working (fell apart - Weird!) and removed the cables and straightened them. Tested all vacuum components and they all worked !!! Then I went looking for the heater control valve, what a surprise it is nowhere to be found. The question I have is do I really need the darned thing? I realize that it will stop the flow of hot coolant to the heater/A/C box, but is it that much of a difference if i'm not using either? Also, is it normal for the fan switch to only have slow and medium speeds without the A/C running?