I have a 92 civic ex and I had gotten a Dx knuckle to replace one of the fronts but now the brake caliper bracket wont even fit all the way over the rotor and the holes for the caliper bolts domt match up. Are they not interchangeable at all?

 

DX knuckle is smaller IIRC.

 

No, they are not interchangeable.

 

EX and SI Civic and DC Integra will be interchangeable.

DX, CX, VX have smaller bearings and smaller brake mounting ears.