You need to multiply 300m by 100cm since there are 100cm in a meter. You should be able to solve that mentally.
300m
30,000 cm
This WEBSITE has the answers as well as pictures and a step by step: http://theswampbbs.com/300m/plugchange/default.html
Oil change is due.
You should change the oil every 3 months of 3000 miles.
4.5 quarts
Carefully remove the lens then bulb
5 to 5.5 quarts
300m
300m is 0.3 km.
It's 253HP for the standard 300m with the 3.5 (all 1999-2004 3.5's were "high output" used in the 300m) It was 255 HP for the 300m Special (a sport tuned edition of the 300m).
Change your input speed sensor. They are cheap at Napa -- and easy to change