You have to do it on the creation side.
Create one TOC. Using Windows Explorer, copy projectname.hhc
to a location outside the project.
Now go back to your project and change the TOC to the way you
want the second TOC. Again, save a copy of that so that you know
which projectname.hhc is which.
Just drop the required TOC in before you open the project and
compile.
How different are the two TOCs? Could you not apply
conditional tags to the contents so that you can include / exclude
whatever you want.
You might also want to consider RH7 where you can have many
different TOCs within the project.
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