Mine was the same way. Flopped side to side, banged against the stops, but I couldn't detect any slop, trying to rock the fork sliders. I 1st retorqued the bearings. Helped for awhile. It didn't last. Next, replaced the bearings. Life is good, Note: the 1st time, I went by the book, using the rubber washer & their torque specs. The symptoms quickly returned. I found the jam nut & bearing pre-load nuts had backed off
I talked w/ my Yamaha mechanic about this. He rides a Roadstar & has wrenched his whole life.( I trust the man) He told me how to re-assemble the steering head w/o the rubber washer & why. I've talked w/ factory trained HD mechanics about this also. All said basicly, hand tighten the preload nut until the fork will barely turn.Then apply lock-tite & tighten the jam nut. Sometimes the tangs on the washer line up, sometimes they dont. I've had no problems with the locking pin aligning with the hole in the upper triple clamp. As far as loose tins, I just bend the tabs up alittle if needed.
The purpose of a jam nut is to mechanicaly "lock" the 2 nuts on a threaded shaft. With the little to no compression required for the rubber washer, the only thing that is keeping the pre-load nut from backing off is, THE PRE-LOAD NUT
While others may disagree with my method, I've ridden over 2000mi in the last 2 weeks. I just checked my fork yesterday, life is good