you can go to the dealership and get one
or
you can get a chiltons or haynes manual at the auto parts store
or
the fuse box lid should have a layout telling you what fuse goes to what.
with a test light or multimeter with ignition off pull the fuse you think
you want to use place one probe (red lead on multimeter) on either side of
fuse while the other lead (black on multimeter) goes to a known ground. if
either side is hot then go to your second choice fuse and continue until you
find what you need. Some vehicles usually leave an empty spot or two for the
addition of options. again test these . the whole process takes about five
minutes

"The moderator" wrote in message
...
I have a 2002 Ford F150. I want to wire in my CB to a wire that is only
hot
when the ignition is on. Where can I get a diagram of the fuse box that
indicates which wire is the correct one.

Thanks in advance.