Here's the deal.

As you see in my sig, I have been plugging away at this carpC for quite some time now. During the last few (4) months, there have been some financial shenanigans that have prevented me from moving further.

No more.

I have access to $1500 in the form of a no-interest, non-CC, guaranteed loan. There is absolutely no way that I am spending all of it, but I do want to finally get the majority of this CarPC behind me.

That being said, here's what I have, what I think I need, and what I want to do:

I have:
PC built and tested (I've been using it as my main PC for 5 months, could actually use a cleaning out...) PC is in Athenatech Newegg case. Biostar M7NCG w/ a Athlon Mobile 2200+ low voltage unmodified.
BU-303 GPS receiver
Hi-Gain WiFi antenna (cheapy Hawking, I might replace with something a but easier to mount)
Aux adapter for stock Honda head unit
RCA to 3.5MM cable
DIY Grounding kit installed in car (Batt, engine, and fuel rail all grounded to chassis)
Laptop CD-Rom (if I can find where I put it...)
Mini (kinda) keyboard
MapPoint set up
Frodoplayer set up

I need (I think):
Screen (Was thinking DWW-7VGA, I am out of the loop on availability. I know Arwen has them even when the site says he doesn't)
Opus 150W PSU
POL PSU for screen (POL supplies are a relatively new concept for me, explanation would be wonderful. Is this just another PSU to only power the 5V rail?)
Wiring for system (mount in trunk)
Mouse solution (touchpad?)

I am trying to do:
A stealth install. I want as little out of the ordinary to be seen as possible. Crime is a bit of an issue where I am at, and although I will be taking the necessary precautions (i.e., taking out a policy on the system) I still don't want some gaudy install to stick out. I also wouldn't mind mounting the laptop CD-ROM in an enclosure in the glove box. I figure I am going to be out at least 700 worth of parts alone, not including the wiring.

I ask that you point out the things that I am obviously overlooking. I have never done something like this before, and I want to make sure that before money starts changing hands, that I have all my bases covered.