I would agree with what you said David, about the value of the 1989 B6's being driven down by the more recent releases.
I also have one of the 1989 releases and it is a good runner.
As with everything, caveat emptor/buyer beware.
I would suggest that anyone interested in the 1989 release look for descriptions saying that the locomotive actually runs or runs fine. There are enough of them listed on eBay to allow for weeding out the ones that might be risky purchases.
To the original poster, hope the shims work and nice work-around offered by GRJ.
Tom