I think you need the extension for your linkage. I am putting front disk brankes onto my cruiser. I have a fj60 booster I am putting on my 69. I need a linkage extension and a booster extension. Meatal Tech is suppose to have them(booster extensions) ready to sell by the end of the month. should be $35 to $40. I have not quite figured out what to do about the linkage extension yet but you can search and there are several options out there.