I removed the bar and replaced the tramp on my 1976 5.2 and it still is together and sailing today. I initially tried to put a SS rivet thru the straps, but they got sheered off, or even worse, weakened the strap. I eventually just snugged up the beam starp and watched them closely. d dont recall them sliding out of place, but they definitely flex enough to sheer the rivet and weaken the strap.
Good Luck,
David