How to Install with saving Build RPATH ?

Our current packaging process deeply relies on the fact that all the binaries and dependencies are being built into the same /opt/stuff directories that they will be placed into upon “installation”. Yes, I know that it sucks and is a bad practice.
I was trying to start slowly and do not replace the process completely with cmake --install from scratch; just make it put everything into a single install/ directory and then make old build scripts look for files in there.

However I cannot find any option to make cmake do not touch RPATH at all. By default cmake completely stripes any /opt/stuff links from the resulting binaries. If I use INSTALL_RPATH_USE_LINK_PATH it only adds some of the paths that should be there, but not all. There is BUILD_WITH_INSTALL_RPATH, but it is about reverse situation. Can I make Install basically copy files without any additional voodo - and without resorting to actually install(CODE cp ...)?