alexander,
Thank you! That did it.
I was confused by the logs (which seem to show just the pre-NAT addresses), and the SRX flow diagram, because I assumed that the Static NAT step did both source and destination Static NAT. I "get it" now, and see that the Static NAT step just works on the dest IP, and Reverse Static NAT just works on the source IP.
The logs were what confused me the most, though.
Thanks again!
...Ralph