Thanks for all of the suggestions we have received. If I had only known
that talking about ARIN on NANOG was the hot button, I would have
pressed it a long time ago 
I do have some operational factoids to add - my prior post was
incomplete.
We are multi-homed in a carrier neutral data center. It is imperative
that we have our own IP. I do have some small bits of CIDR from other
ISPs and have already migrated some of the problem customers to other
blocks, but I am not meeting my SLAs with those customers, because we
guarantee multiple paths.
On IP that belongs to an upstream of ours, traffic only comes inbound
through that upstream. That is a problem.
Sorry if talking about ARIN is off the topic of this list, but the 69/8
CIDR is "broken" (in customer terms) in lots of places on the internet.
ARIN is the one assigning it. If they keep assigning it before
everyone's access policies recognize it as valid, this "non-operational"
issue is going to cost a lot of people a lot of money in wasted time,
effort and resources.
I know it has been very painful for us.