Unless you're handy with a slim jim, might have to bite the bullet and call a professional locksmith, especially if you care about possibly damaging the car
You will need to call a locksmith unless you want to brake a window.
They are built inside the latches.
Yes.
It is screwed to the inside of the under dash fuse panel.
No.
1999 300m
5w30
take out the screws on the inside
10W3010W30
It has a belt.
5x114.3
You can find a wiring diagram for a 1999 Chrysler 300m in the vehicle's owner's manual. You can also find it at various auto parts stores.