Hey guys,
The bridge I made lifts up and out - thus it doesn't connect to the "mainland" track - there's about a 1/16" gap. Electrical connection to the bridge tracks is made via plugs underneath the bridge - wired up thru and soldered to bridge tracks.
The girders are from Lionel's Right of Way bridge kit, available on secondary markets.
BTW: My bridge is just over 36" long ~ the Lionel bride is only around 30" which would have necessitated me narrowing the walkway. My bridge is very strong - double layers of 3/4" plywood.