Those cars are foolers. You wouldn't think a little 110HP six in a great big car like that would do anything, but in practice they have all the power you need.
For one thing the car is a lot lighter than it looks, only about 3500 Lbs. This is less than a Ford Taurus or Toyota Camry and not much more than a Mazda Miata. I'm not kidding.
Furthermore the flathead six is all about high torque and a broad powerband not all out horsepower.
It has around 200 ft lbs of torque. This means you won't have any trouble keeping up with traffic, up to 70 MPH anyway.
You can use ordinary 10W30 motor oil. I suggest adding 1 quart of heavy duty diesel rated motor oil at each oil change simply because modern oils are skimping on the additives and the old model engines can use some extra protection.
You don't have to find any special oil, non detergent oil or any of that apcray.
Detergent oil was introduced in the late 40s and chances are your car has never used anything else.
The transmission and fluid coupling call for #10 motor oil. But you can use TDH tractor fluid, ISO32 grade. You can get it at any auto supply or farm supply store.
There is nothing wrong with a 6 volt system. You don't have to change anything just repair whatever is bad. Your car will start and run fine.
You might want to check out the AACA forums. They are all about keeping them stock and on the road. Some of the regulars in the Chrysler section have years of experience with cars like yours and drive them thousands of miles each year, on the stock engine and trans and 6 volt systems.
http://forums.aaca.org/ubbthreads.php/ubb/cfrm
