torsion bar hight adjustment bolts and block

i dont know any thing about the application or the car really. but is the block the thing thats threaded? if so try and run a tap down the hole to rethread it

yea '68 was a while ago .. well what you probably have is a corroded adjusting bolt (hence no fine threads ) so it slipped through the hole clear up to the retainer . Well If you measure the bolt Dia. where the threads are good V/S where the threads are bad you could probably determine if the bolt was at fault. Same with the retainer . I allways thought you were supposed to take he preload (twist) off bar before losening anything else . I heard one time about thirty years or so ago somebodys bolt blew out da ho and went a quarter mile fore breaking a window ! Hey !!! Be carefull !!

your talkin about the suspension end of the bar I assume . Year one , specializes in quality resto parts for about everything I know for certain they have the bars, I'm gonna assume again they would have the rest of the required hard ware but if not there's always the junk yard .