Don’t be misled by the term “overhead” into thinking that if you use overheads, they have to be high up or far away. In most cases, the purpose of overhead mics is to capture a balanced image of the entire kit that you can use to complement individual mics. There is no exact height for your overheads that we can recommend, it depends on how large your kit is, how loud the cymbals are in relation to the drums, where the right balance point is, the overall drum sound you are trying to achieve, and so on. For example, you may find that the most balanced image for your “overheads’ is actually with the overheads down low, close to the toms. Experimentation is key. Try moving the overhead mics up and down, and experiment with different stereo and mono miking techniques (there is no rule that overheads must be stereo) and spacings, as well as pan positions and levels in your mix.
As a side note, some recordists confuse overheads with “distance” or “room” mics. If you are recording in a great room, or you want to capture a huge space, you may want some mics really high up, or across the room. But these mics aren’t the same as drum overheads. Your overheads sit right above the kit, to help out with the fullness and balance of your drum recording, not to capture the room sound or ambience.