"Douglas St. Clair" wrote

I'll only give an opinion on the questions that I think I might know
something about, but of course, it's your job to decide if I'm f.o.s. or
not. *8-)

2. Ignition Control. What electrical components should require the
ignition
to be on for them to work? I'm guessing the bilge pumps are the only
items
that need constant power in order to leave them in "auto" mode". What
about
the blower: is it ok to leave the ignition on for four minutes without the
engine running? Is there any reason not to wire all the switches as
always-live?

You can't really put a lot through the ignition switch. You can add up the
amps that the various switches control and then compare that to what the
ignitions switch is rated for. In my case, I've got everything hot, nothing
through the ignition except the tach. I've been toying with a master
switch, but haven't figured it out yet.

3. Are there any websites or other resources out there that show ideal
wiring diagrams for a relatively simple boat like this? Right now the
wiring is spaghetti-esque from the 34 years various contributions of
different owners. I'm a neat freak, and need to get everything "in
order".
I just don't know the best practice for this. I'm thinking I'll need one
bus bar for the negative lead, and two hot feed fuse blocks (one is always
on the other is ignition switched). From the fuse blocks do the
individual
leads go to the switches then on to the various components? Are there any
special considerations for the gauges (tach, volt, dc, temp, oil
pressure)?
What are the connections for the gauges, is it simply negative, hot, and a
feed wire from the engine?

OK, this is very basic and I'm no electrician. But, over the past couple of
seasons I've pretty much either added and/or re-wired my boat with just the
sort of accessories you have in addition to a couple of others.

The basic principle I've learned and it seems to be an indication of a clean
installation is to run everything through master grounding and fuse blocks
mounted behind the dash. Your main hot wire goes from the battery to the
fuse block and the main ground wire goes to the grounding block. Then, the
power and ground for each of your gauges, accessories and/or switches gets
wired to the blocks' terminals right there behind the dash. It organizes
things up nicely and makes troubleshooting pretty easy.

Make sure you get blocks with plenty of terminals so you don't run out. I
chose a fuse block with the kind of fuses that modern cars use (squarish
plastic things with two "legs") - as opposed to the tiny glass tube kind.
If you can, it's best of course to somehow label the fuse and ground block
terminals. I had a hard time doing that so I just put a tape label on each
wire near where it entered the blocks. I have this vision of making a
diagram, like your car has, but haven't gotten around to it.

All of your accessories should have an amp spec for fuse selection (it might
be in terms of watts, but that's an easy enough calculation). A lot of mine
didn't or weren't readily available so I asked around and/or looked at
similar products in the store to get an idea.

All of this may go without saying, but it wasn't the case with my boat when
I started. I had a bunch of wires running back to the battery with in line
fuses, no fuses, etc. etc. A real mess.

Another option is to buy a switch panel from the marine suppliers - that
might suit your needs. Might not serve the look you want. Also, as was my
case, it seems each accessory needs a different sort of switch.
Grissy.