Those Tigers are gorgeous you've done a very good job. I notice you like to build tanks the way I do.. gut em and load in the steel, very nice.

Couple questions... can you post a link to where you got your motors, or their specs? I'm really picky about motors and won't buy anything that has lacking information :P

Do you need anything extra running 4 speakers?? I'm not sure a Clark board can handle the extra draw, assuming you're wiring in parallel.