Well, I dis some serious looking at how to get a hose or wire through the firewall and found a way. I can take the footwell panel out and get access to where the electrical wires go through the firewall to the underhood fuse box. Under the hood, I can route a wire into the fuse box through one of the nipples that is empty. If I take the top of the fuse box out that has all the fuses attached, I can poke a wire through to the inside. I found a link to a small digital guage here
http://www.speedshop.org/store/Scripts/prodView.asp?idproduct=20
Where do y'all think. I would rather have an analog guage but I think this one would fit better with the interior and be small and hideable if I decided to hide it in the ashtray.
I will take the Dawes device apart and check it out.