Hello, I own and built K2 # 3706. BTW: It has run flawlessly since built in September of 2003. I'm going to proceed with purchasing a KP100 and KAT100 soon. I am also ordering the CW keying bandwidth mod kit. Are there any other upgrade/mod kits needed for upgrading my K2/QRP to the K2/100? 73, John - KI7V