You could get one of those low profile grease fittings that Tom has pictured in his instruction for replacing u-joints.

 

Good ideal on the low profile grease fitting.
I put the little hex sealing screw back in today.

Well, I have learned from you guys and reading another post that my drive shaft is probably an original drive shaft still on the truck.
I have to watch the rear u joints as those can not be greased.

 

I wouldn't worry much about that fitting since you are still running on the bad factory shaft. You need to rebuild or buy an up-graded drive shaft before that one fails, and it can.