Nick, I definitely agree with the recommendation of adding access hatches. I'm in the process of putting them in on my layout too. We're not getting any younger, and crawling across benchwork isn't going to get any easier. If you're looking for a good drawbridge, Jim Ballmann of Stainless Unlimited makes a great product.
"I will make them pivot and rotate to open like a door similar to what John Coy uses on his layout"
Greg, I don't mean to hijack this thread, but anything you could post on this type of removable section would be great; I'm working on the same idea for my layout. I searched youtube and the forum as you suggested and came up with nothing.