there should be a small short pin that holds that top pivoting stainless steel bracket in place. On the old cars, I believe you had to take the end cap off each end of the traveler to slide out (by shaking) the pins. I'm not certain how you remove them on that traveler though - if my memory serves, the pin might be threaded and have a small flat-head slot on it...you would stick a small screwdriver into each end of the car to unscrew those pins.

Once you have that stainless bracket out of the car, you will have full access to the heads of the screws. Use locktight when putting it back together.