How to install just the ODBC driver in Windows?

Is it possible to install just the ODBC driver without installing the
rest of IBM i Access or ACS?

Also, if IBM i Access is already installed, but without the ODBC
driver, is there a way to install just the ODBC driver without
reinstalling the rest of IBM i Access?

I had downloaded IBMiAccess_v1r1_WindowsAP_English.zip and extracted
the contents. In the Image64a subdirectory there is a bunch of stuff
that looks relevant. If I run the setup.exe, it complains that I
already have IBM i Access installed and refuses to continue.

What now? I'm guessing that even if there isn't a script or installer
for just ODBC, there are manual steps I can do.

John Y.