Thought I would share this in case anyone is looking for ideas for a moveable entry bridge for their layout.
I used an Atlas double track through truss bridge, which is a beast with 4 steel bars going through it. I mounted it to 3/4" plywood and used some 1/2" steel tubing from Lowe's as stiffeners. I welded a couple of pieces of steel angle to the tubing and used a piece of angle welded to a hinge on the nearby door frame to hold the bridge in the open position. Some cabinet clips hold it down and in position. I'll keep refining it but for now it's functional.