I actually have never redone the needle bearings in the rear linkage on a zilla before. I have only owned mine for about 6 monthes.  When I have dealt with needle bearings, I did just like you said, put a lil grease in there to hold em in place and be patient.
I dont have fat fumble fingers, but I sometimes have drunken fumble fingers, and I usually get the needles in place first try.
Something that would be cool is if we could find replacement needle bearings that have a cage, similar to a wrist pin bearing. Just need to measure them up and do some homework.  Think no more searching for lost needles rolling around the shop floor!