Sancho is a Spanish name and it means Saint. In slang it means the other man, a guy a girl is cheating with. Sancho means sancho in English as well as Spanish. Pearl Yamada.
The general rule of thumb for a horizontal smoker is that the firebox should be 1/3 the size (volume) of the cooking chamber. These are just guidelines based on years building smokers but your mileage may vary! Cooker Chamber Type & Size.
A medium size stove with ~2.3 cu ft firebox may be just enough but a larger stove with ~3 cu ft may also be warranted. For example the PE Summit (3 cu ft) has a depth of 18. The large Osburn 2400 needs a minimum of 17 1/4 depth.