Hi vicpopo
What about the DBK-HT Dual Motor Drivers that Thanos provided a link to -
see eBay Item Number - 221043792022
Quote "The DBK-HT Dual motor driver is based on Dual BTS7970 chips forming h-bridge capable of 68A currents. These chips have integrated protection against overheating, overcurrent and overvoltage."
Thanos has tested one of these, although not with one of the 180W motors, but looking at the specification these boards should work Ok.