[Daryles]

I bought a Lock N Lube pistol grip grease gun (one handed) with locking grease coupler. Works great.
As mentioned above sometimes you need to take the weight off the axle by jacking up your rig.
The bolt needs to be installed so the eye is at 9 or 3 o'clock position with weight on wheels.
With weight on wheels, Mark the Shackle with a horizontal line on either side of the bolt head with a sharpie.
This will show you how to align the bolt in the Shackle with weight off wheels so the eye will be at either 9 or 3 o'clock.
If you have to remove a bolt, mark the head on the side of the eye for future reference.