As someone mentioned earlier the max you should tow shouldn't exceed 75-80% of the kerb weight of the towing vehicle 
  
The scooby may well have enough grunt to pull the Zed but not enough weight to be safe  
  
Many of the TOWBAR sites do a matching service (for caravans) but if you found something that matched the weight of the Zed and trailer combined you could use that as your numbers 
  
Check out towsure.com 
  
  
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