This 1500h mark you are referring to gives an exemption from the approved course only if you have an ICAO ATPL and (from Bristol’s webpage):
* more than 3000 hours total time on aircraft of more than 30,000kg AUW
* more than 1500 hours pilot in command on aircraft of more than 30,000kg AUW
* type rated on an aircraft of more than 30,000kg AUW
* more than 500 hours total time on the aircraft above
* able to complete a flight test on the same aircraft
Since you have a FAA CPL a complete course must be done. If you meet the JAR ATPL requirements (500h mcc and so on..), an exemption could be possible. For ATPL requirements check out JAR-FCL 1
http://www.jaa.nl/publications/section1.html