how to patch in port with NO_BUILD?

[Miroslav Lachman]

I know how to prepare a patch for ports which extract some source files 
and then install them. But is there any way to patch file in port which 
uses NO_BUILD and

do-install:
         ${INSTALL_SCRIPT} ${DISTDIR}/${DIST_SUBDIR}/${PORTNAME}.sh \
               ${STAGEDIR}${PREFIX}/bin/${PORTNAME}

Is it namely databases/tuning-primer. I cannot find any doc how to apply 
patch in this case.

Kind regards
Miroslav Lachman