You don't need to use the switch at all. Probably both units come with in
line fuses. Just attach both fused wires to the hot side of the fuse block.
Look around and you will find a common ground point. It might just be a
screw post. You should see a few black wires all coming to that point. The
keep alive voltage for the radio presets and clock is usually a yellow wire
with an in line fuse. That should go to the same hot point as the other
fused wires as long as there is not a master off switch or battery
disconnect. Read all the instruction sheets before you start. Fire the units
up before you mount them permanently. You want to make sure your compass
won't be affected by the units where you plan to mount them.
JIMinFL

"Melandre" wrote in message
oups.com...
I just got a new boat which came as plain as you can get. Just a
smaller 18' bowrider. I have now purchased a basic Garmin fishfinder
and a Alpine marine CD player/stereo and a couple of speakers.

Now the hard part: installing and wiring these gadgets. So here are
some of the questions that come to mind:

1) as far as I can tell, I have only one, unused, "Accessory" switch on
the console. Should I plan to connect the fishfinder to that switch?
Am I right to think that the stereo does not really have to be on a
switch?

2) How do I connect the stereo to the battery? Should it be done at
the battery terminals or is it OK to splice the red battery wire (or
connect it to the fuse box?)?

3) there is no metal near the casing around the CD player/stereo. What
should I ground the stereo's black wire to? Am I correct to assume
that wiring to the stereo's own harness is not a good idea?

Andre