No they are different...if I recall correctly the 96-98 pedal assemblies have 4 holes. The 99-04 have 3 holes and 1 stud. But that's the only difference...I have a 97 hydraboost in my Fox with a 04 pedal assembly. I just knock the stud out and use it. If you have a 99-04 hydraboost and are using a 96-98 pedal assembly then you will just need to use a bolt in the 4th hole.