Are you saying there was a vibration then you had the tires balanced it went away then it came back?I got my 1.25" spacers off ebay (hub-centric also) - this was back in December, so I can't remember the name of the vendor. I did experience some vibration around 60-70mph, which would go away for awhile after a balance... but man, they really made a difference visually!
hmmmm...sounds to me like if it vibrated, then went away when the tires were balanced then would come back, that its not a balancing issue and more of a wheel working its way "un centered" if you will....that the whole thing would be centered and vibration free at first but after a while would settle back to where it was off center, whether it was hub to spacer, spacer to wheel or whatever....masterdiag, does that make sense? how im describing it? i think thats the thought you are having too..Are you saying there was a vibration then you had the tires balanced it went away then it came back?