You can't put a normal adjustable cam gear onto a RB25 inlet cam, they are a special cam with a single bolt running into them to hold the VCT in place. You can however buy a special Greddy cam gear (I think it was Greddy, can't remember now) that makes it semi adjustable.
As has been discussed in plenty of threads. Losing VCT is stupid for a street car, it is a damn good thing. You should do whatever it takes to get it back.