Depends. If you plan to use Wilwood Superlite 4-piston calipers and rotors that fit under 15" wheels, my experience is, you don't need caliper adapters. The Wilwood caliper bolt spacing is wider than the stock calipers, so what is needed in this case is to ream out the Wilwood caliper mounts for the stock Pantera caliper bolt size, then drill a third hole below the stock lower one. The caliper bolts are in the back side of the steering arms. Tap the new hole to the stock metric thread and, on some steering arms, build up the area around the new hole with weld for resistence to cracking as it will be very thin on one side. Mount the Wilwood caliper and measure the thickness of spacer you'll need to center the new caliper. The spacer can be aluminum; welding on the butt-end of the steering arm to build up a 'boss' is relatively safe since the steering stress is at the other end of the arm.
If you want to run large-than-stock diameter rotors, the calipers must be spaced outward, and you will need a caliper adapter. Fooling with brakes is serious stuff; I suggest you contact a vendor who has worked out all the engineering on this combination.
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