Hi Captain Bob, welcome to the forum from Germany!
The PO has put a GPR exhaust on my Conti. I don't know if this measure increased the power but certainly the GPR wheights only half of the original exhaust. Once you removed the Db eater it at least sounds faster
The GPR has a road legal certificate which is important in Germany - but not important for you...
...so you might look for a cheaper solution. May the sound be with you!!!
Cheers from the Bavarian Outback
Ralf
P.S. Could you post pictures of the Conti and the Woodsman?