gearbox fill-up?

Wheres the best place to fill the gearbox with oil, is it the 17mm bolt beside the shift lever, and is there a level indicator?

I usually pull the plug from the level indicator hole and then remove the shifter. After the shifter is out you can pour the fluid directly in thru the shifter hole slowly until it starts to drip from the level check hole. Put everything back where you found it and your done. They make pumps to fill them thru the level plug but I don't have one so I do it this way. There is less laying under the truck this way too, lol.

ok but which one is the level indicator plug??

I can't remember which side the level plug is on, its been about 4 yrs since I sold my old Hardbody. Check the service manual, it should tell you. The manual will probably have a pic of it too.