OK... I've manually accomplished the following. Hopefully someone will see what I'm doing and help provide a push in the right direction.

Using Zip Codes from a modified version of our load planner spreadsheet, I was able to use the Data import wizard to import push-pins that seem to show the appropriate locations. That data is sufficient for planning mileage and route information. I'm still trying to figure out how to plan a route using pushpins though. The search continues.

I have questions though:
How do you tell MapPoint to look at a specific subset of the data to import? ie: a specific cell range containing a list of zip codes that are already in the appropriate order.

Any thoughts? I know the MapForums hive mind already has some genius who has figured all this out, so I'm sharing my progress here in hopes that that person will have some good input.

TIA, again.