Two layouts ago and 2,600 miles away in PA, I designed a lift out bridge with two interesting features.
First, the bridge was held in place with cabinet latch magnets which were wired at one end for power to the center rail and outside rail power at the other end. You can see the wire soldered to the magnet housing in one of the pictures. The other end (metal plate to which the magnet attaches) is soldered to and wired to the bridge track.
Second: I protected the approach tracks with normally open push buttons at each end which cut power if the bridge was out.
To stabilize the bridge, brackets were attached to each side:
Hi Stangtrain, that's a very cool bridge! The safety switches are a heads up idea. Oh man, without the switches if you did forgot and ran that Big Boy off the layout, that would be painful. Speaking of Big Boy, I can't tell from the photo, but is it LionMaster or Scale? Nice work!!!