I just ordered new connectors for my old Excal with the sword on it which is just like yours. I talked to Ralph at
http://www.sunraydetector.com/ and he informed me that pin 3 and 6 are both ground wires so you can tie them together. He won't be quoted on that. Obviously you perform the work at your own risk. My excal already has a WOT coil on it and once I get his connectors I will swap out the crappy waterproof connector that came with it for this one. The good thing is since I had Minelab do the work a year ago or so all I need to do now is match everything that’s there to the new connectors.
I also agree that Minelabs position has changed since they were bought out by Codan. However what I heard is that they no longer did these modifications anymore because people were doing those themselves and then when they couldn't get it to work coming back and saying Minelab did the work. Minelab had no way to track it. They open themselves to a lot more liability when performing these modifications and while I still wish they did them I understand the logic.
On the PI topic….Personally, I would rather dig less gold and NO Bobby pins than more gold and every bobby pin I pass over. I can hunt for 9 hours with a VLF machine before the body starts screaming for its two best friends…. Tylenol and Motrin. I was lucky to last 4 hours with my PI. I want another PI in my arsenal, but only for certain places.