Shouldn't be hard. You'll need a brake booster, and a few other parts. You'll probably want to change over to disk brakes aswell if you don't already have them. There are guys here that have done this, I haven't so I don't know the specifics. But it can be done.
68 fastback, 390 4V premium fuel
80 5.0 hatch, just finished
91 5.0 coupe, daily driver
84 RamCharger 4x4 extreme mudsliger and winter junker
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