Not sure what you mean by 'set'. I have 2 terrestrial tuners, what do I need to do to 'set' them? BTW there are a few other timers in the list already that overlap.
As a separate point: I have always assumed that scanning on one terrestrial tuner serves both tuners. I mean it isn't necessary to scan for channels on both? Since other Timers manage to overlap seems to suggest one scan is enough.