I recently bought 4 37D motors (over the Labor Day Sale, sweet deal), but I didn’t do my homework well enough and they turn too slowly. I’ve opened two motors so I can’t return them. I’m wondering if it is possible to simply purchase and install a gearbox with a lower gear ratio for these motors? I need to know pretty quickly because I’ll need to return the other two motors later this week if I can’t swing that. Maybe the possibility of sending all 4 motors back to have a different gear box installed if that can’t be done in a basic workshop?