Just a note to follow up on the issue of permanently removing the tripod collar.
I called ahead to the Nikon Service Centre in Hong Kong and they said they could remove it, but they weren't sure how long it would take. Earlier this week, I walked into their service centre and explained to them I wanted the collar removed. The technician immediately surmised it was for UW use, and 30 minutes later the job was done. The collar was returned to me in one piece. Labour cost was the equivalant of about US$ 30. I was very impressed with their prompt and efficent service. I wouldn't have minded if they took a little longer, as I needed more time to browse through all the neat Nikon gear on display.
A question though: Upon removing the collar, they noticed that there was an opening in the side of the lens barrel where the collar had been. They were concerned about leaving the opening exposed, so they put some tape around the barrel to cover the opening. It's not clear to me what the opening was for (access to lens gears possibly?), but is the tape good enough, or should I be concerned?
Thanks.
Michael.