Thank you all very much for your suggestions.  Just wanted to give an
update here.  I called Rancho and they did indeed seem like a
fantastic choice.  I talked to Maxed Performance, another list
recommendation, who also recommended Rancho, and decided to use Maxed
to pull the trans and have a look at my hesitation-on-acceleration
issue.  As Stacy mentioned, Rancho is running quite a backlog (3
months), and needs to have the transmission sitting there to have a
place in line.  Hopefully it will be worth it.

I had planned to drop off the van today, but it went downhill fast.
Seems like maybe the transmission input bearing was going.
Eventually, things got bad enough, the clutch seemed to be rubbing and
making occasional squeaks, and it was occasionally impossible to get
into gear with the engine running.   Maxed was accommodating despite
their tough parking situation, and I limped the van north and dropped
it off last week.  The atmosphere at the shop was calm and organized,
and Ed's "bedside manner" was a big improvement over the shop I had
been using.

I guess now all the other machines in my life can get some overdue
attention.  :)

Alex