Kyle,
You would blow the light bulbs out first and the fuel guage would follow and shortly there after coil would go. UNLESS, you put on a voltage reducer on the system. The starter as stated above will handle the 12 volts, with no problem, just keep in mind only for short period of engine cranking. I wouldn't think the voltage regulator would handle the 12 volts either.
Last the generator wouldn't do a good job handling putting 12 volts back into the battery. the battery would probably only be charged to 6.5 volts or so. Don't know for sure, never had a chance to check this theory out. Just an assumption on my part.
I found out that all of the above is true, or at least the previous owner found it out first hand. Every single bulb was out and the fuel gauge was completely destroyed when I first got my 54-3800 truck.
John N.
