Battery drains over night, new battery was installed same problem. There was no arc/spark when connecting the battery, only 29,000 miles on car

Usual culprit is boot (Trunk) light.If not, try disconnecting battery and if a spark jumps as you take the lead off it shows there is a power drain. If no power drain it points to a faulty battery.

A bad switch, a short of a bare wire touching frame. Starter switch
bad sounds like a fairly heavy drain. I'd try to connect and disconnect on very dark night see if you see any other arcing any where around the car and inside. Electrical problems are difficult
to chase down. If you see other arcing that is probably the location of the short to frame. A high tech way is to use Infrared
camera. A distance temperature meter may also work. It may show where the short is by showing a hot spot or a higher temperature than the surrounding area.

one way to do this is to wait till its dark and get to the fuse block and pull each fuse one at a time slowly , the one that is pulling a load will have a large arc or like a spark to it then its just a matter of tracing out the circuit !

Small sparking is not normally a problem. There are items in the vehicle that required power at all times. These can cause a spark upon connection of the terminals. There could also be a drain on the battery that may require investigation, especially if the battery drains down on a regular basis. A large arc or flash can be the result of hooking the battery up in reversed polarity or a major short in the electrical system.

Could be just a need to reset the "check engine light", normally this is accomplished when the battery is disconnected for 15 minutes...If your Lebaron is now running smoothly, have the alternator battery tested for free at most auto parts stores for peace of mind. Auto Zone can also read the check engine light code for free. Tight belt, good tensioner pulley, good alternator, you should be in business. Most likely no harm done when the arc occurred.

First step have the battery tested, a bad cell can cause a internal drain and kill the battery, if the batt is ok then check for interior lights like visors that stay on or interior light that come on by themselves at night due to defective door switches.

best way to see if it is a spark plug wire or bad spark plug connection is lift the hood at night you will be able to see the arc then replace wire, plug or maybe just tighten a loose spark plug. car cranking slowly check battery voltage or battery is getting weak low amperage.

Yes your ignition switch can be bad.

Go to the battery and disconnect the cable...a dark garage is helpful, look for arc from the battery cable as you disconnect and retouch the terminal. Now go to the fuse box and take a suspected fuse out and go back to the battery cable and see if the arc is still there. Replace the fuse and try another one. Repeat this process until the arc stops. You now how found the correct fuse. Now look on the fuse panel or owners manual and see what that fuse supplies. Now start unplugging the devices and repeat the battery cable touching until the spark stops. You have now found your problem your a genius. Now all you have to do is either unplug the device that is causing the drain, or look for a bad connector at this device or replace it, but the ball is in your park now.

loose or broken  connection at arcing point