ApacheFiend,
Good question. Some of the lighter AD trucks have floating bushings in the spindles...yours isn't an AD but a Task Force, so I don't know if this 'float' deal applies to you.
The OD of the spindle bushing would have a turned groove around its circumference so the grease would find it way in regardless of where it was positioned. Is this how yours is!
If you are not suppose to have floating bushings, and your spindle bores are worn, a machine shop can make new bushings, and true up the bore slightly in your spindles for a nice fit. There might even be bushings available with a oversize OD for just this purpose.
So the answer to your question is, I have little knowledge on this subject and hope a TF guru pops in...maybe Red58!
Stuart