Coolant Flush on a 1998 3.7.

Hello there,

just like to pick your guys brains for any hints/tips you mat be able to give me. Searched the web but cannot find a definitive answer, bits on American sites but unfortunately they do not speak English.  Coolent needs doing, looks like a different anti freeze has been added to the G12 at sometime (brown, want it out) New stuff on its way to me so what I would like to know is,

1) Can you use a flush in the system before the new G12 is added, recommend or not?

2) Looking from the front of the car, is the drain (petlock) on the left or the right?

3)Is it accessible from the bumper vents?

4) I believe there are vents in the bulkhead area, are they easy enough to get at?

5) Any other hints/tips would be greatly appreciated,

thanks,

Dave