I fill mine by removing the floor pan, then removing the fill plug, (which is about 1/2 way up on the passenger side), then remove the gearshift, (by rotating the bayonet lock thing and pulling the gearshift out) and pouring the oil into the gearshift mount until it starts to run out the fill hole on the side.
If you have two people, you don't have to remove the floor pan.
If you have a pump and a lift, you don't have to remove the gearshift or the floorpan.
If you have a funnel with a long flexible snout, you can fill it from the side fill hole after removing the floor pan and the fill hole plug.
Kurt
