Tachometer Problem

Whats up.,
I have an autometer tachometer and i tried to hook it up but had some problems. I hooked the green wire to the blue and grey tach wire in the cluster. The red went to the radio fuse and i tried the back up lights fuse. The white went to the fog lights fuse and the black i hooked to the battery. i had power and the tach would repsond to the rpms but then the needle would go right to 7 grand and wouldnt stay at zero. Then after that i started blowing fuses that i had the red wire hooked up to can anyone help me or does anybody know why its doing that? do i have the wires hooked up wrong? Any help will be appreciated Thankss alot

If you are hooking up an aftermarket tach, you need to cut the tach wire going to the cluster.

* Mod Statement* I know this post may be old, but I am trying to answer the questions with no replies, to get some useful info out there.