I got the T running, but it won't stay running at near idle speed on battery. The Amp meter shows -10 at idle and about -30 when the engine is revved. Does this mean it was set up as negative ground? Or?

put a volt meter across the battery at speed it should read 8 volts or so if is charging. if you
the battery in backwards i would unhook it asap.

If you have a negative ground, as you should, then the ammeter is connected backwards. Swap the wires on the ammeter, but first be sure you have a neg. ground.

I have an 8v battery in it. Recommendation of an early Ford specialist. I just have a feeling it had been set up positive ground.

It should be negative ground.

Right, I know it should be negative. But if the generator is charging backwards because it WAS positive ground, would that give the issues I am seeing?

ensure there is no current draw when the car is NOT running, and there is no spark at the battery post when you disconnect the battery.

you may have to flash your generator:
http://www.mtfca.com/discus/messages/29/50521.html?1205734697

you may have to replace your cutout (if it is not for 8V). As an aside, if your system is working correctly you will not need an 8V battery. Or you may have to replace your cutout because it is stuck closed and you are trying to "motor" your generator which will result in a current draw.

you may have your ammeter wired backwards, though if you really are charging 30A the generator won't last long.

there are a couple more scenarios, but start with flashing the generator.

You are going to need to peck through this and confirm one thing after another without doing everything at once and becoming lost.

If the generator cutout has a diode, there is a possibility that it needs to be reversed, depending on what you need to do. Just adding to your check list.

A quick check for the ammeter wiring is to simply turn on the lights with the motor off and see if your ammeter shows a discharge. Cheers : Bruce