Trouble installing shared library/header to sysroot

[Daniel Kenji Morgan <daniel.kenji.morgan@gmail.com>]

Hello,

I have a package that builds a shared library using autotools.
When built, the shared library and header files are correctly installed to /usr/lib and /usr/include respectively.
They are also correctly populated under sysroot.

I have been trying to change the target directory to /opt/lib and /opt/include only with limited success.
I managed to get the library and header files installed correctly by:

1. Setting "--libdir=/opt/lib" and "--includedir=/opt/include" in EXTRA_OECONF
2. Installing the directories in do_install_append
3. Adding the directories and files to FILES_${PN}

However, I cannot get the library and header files populated into the /opt/lib and /opt/include directories under sysroot.
I couldn't find any existing recipes in poky that did something similar.
Is what I am trying to do actually possible under Yocto?