the electronic auto meter gauges I was looking at, the 5" sizes, were between $225-280 and still required the Hall Effect sender which is another $70 or so ....
those speedos will work off of the ford factory sensor that is on the t5 speedo cable in a mustang for the cruise control. i have one for the capri project that i can show you and we can go down to ecology and get one off of most of the ford rwd cars or trucks. or we can see what a new one costs but then we dont get the pig tail that plugs into it. we should pick up a few of these when we have the chance.
a friend of mine put one of those in his Hot Rod... had it about a week and had to send it back to have it repaired...
I've had mine in for a couple years now and have yet to get it working. Check out these guys for GPS speedo http://www.speedhut.com/
Interesting that two people have been having trouble with the electronic gauges. I want to keep my gauges looking the same, probably will try the auto meter and see what happens.