"I am considering attempting to use the existing radio antenna wire as
"pull wire", by attaching some string to it and then by pulling it
forward. Then I can pull both the regualar and the sattelite antenna
wires back with the string. "
I'd be very surprised if that worked. I installed a new stereo and
amp in my 80 300SD. I ran wires in mine similar to what Bernard
recommended. I don't remember if I went via the tranny tunnel or part
the doors, but definitely had to take out the back seat. These cars
have lots of things like sound deadening/insulation in the way, plus
the route is anything but straight.