hi there, i have just installed 2004 clamps in my 1994 frame. they fit straight in but you have to take into consideration 3 things:
a).the fork distance is longer by about 10mm (not measured exactly), so if you are intent to use your oem fork (conventional wp extreme is it?) you just can not do it with your stock wheel!! the wheel center will be out of the bikes center by exactly the distance difference of the clamps. of course no spacers can do anything because the brake caliper side of the fork needs to have a specific distance due to the disk brake alignment
my set up is : 2004 clamps, 2000 43mm fork, 2004 complete wheel.
my old fork was a 4054 wp.
b). the offset of the 2004 clamps is 22mm
c). you will have to use aluminium shims to reduce the clamps diameter to fit your old fork, be carefull to machine open shims and the alignment on the clamps.
d). a slight mod is needed to fit your old steering bar.
e). the 04 clamps axle is made of aluminium which was an issue (broken) on some racing applications.
thats all!!