disc brakes on a duster

well the lower ball joint bracket fits. the only problem is that neither the spindle or the bracket have threads in them for the bolts. im thinking get longer bolts and some nuts?

the fbody spindles i got the bracket bolts threaded into the bracket. the 73 duster disc brackets have no threads in them.

this is pissing me off. im half tempted to saying screw it and mount skis to the front of my duster and have a stupid fast snowmobile :D