diff --git a/src/Makefile.inc.in b/src/Makefile.inc.in

index 411422d..b5f1662 100644

--- a/src/Makefile.inc.in

+++ b/src/Makefile.inc.in

@@ -65,7 +65,7 @@ LANGUAGES = @LANGUAGES@

 docsdir = ${prefix}/share/doc/linuxcnc

 sampleconfsdir = ${prefix}/share/doc/linuxcnc/examples/sample-configs

 ncfilesdir = ${prefix}/share/linuxcnc/ncfiles

-tcldir = ${prefix}/lib/tcltk/linuxcnc

+tcldir = ${libdir}/tcl/linuxcnc

 # /Standard configure directories

diff --git a/src/configure.ac b/src/configure.ac

index 942e35b..38eb8b5 100644

--- a/src/configure.ac

+++ b/src/configure.ac

@@ -705,8 +705,8 @@ else

     EMC2_SCRIPT=$EMC2_BIN_DIR/linuxcnc

     EMC2_SUFFIX=""

     EMC2_ICON=linuxcncicon

-    EMC2_TCL_DIR=${prefix}/lib/tcltk/linuxcnc

-    EMC2_TCL_LIB_DIR=${prefix}/lib/tcltk/linuxcnc

+    EMC2_TCL_DIR=${libdir}/tcl/linuxcnc

+    EMC2_TCL_LIB_DIR=${libdir}/tcl/linuxcnc

     EMC2_LANG_DIR=${prefix}/lib/tcltk/linuxcnc/msgs

     EMC2_PO_DIR=${prefix}/share/locale

     EMC2_HELP_DIR=${prefix}/share/doc/linuxcnc

@@ -928,7 +928,7 @@ then

     AC_MSG_ERROR([fuser not found])

 fi

-AC_PATH_PROGS(YAPPS, yapps yapps2, "none", $SPATH)

+AC_PATH_PROGS(YAPPS, yapps yapps2 yapps2.py3, "none", $SPATH)

 if test $YAPPS = "none"

 then

     AC_MSG_ERROR([yapps/yapps2 and not found])

@@ -1609,7 +1609,7 @@ fi

 AC_MSG_RESULT([$PYTHON_TK_VERSION])

 AC_MSG_CHECKING(for site-package location)

-SITEPY=`$PYTHON -c 'import distutils.sysconfig; print(distutils.sysconfig.get_python_lib())'`

+SITEPY=`$PYTHON -c 'import distutils.sysconfig; print(distutils.sysconfig.get_python_lib(plat_specific=1))'`

 AC_MSG_RESULT($SITEPY)

 AC_MSG_CHECKING(for working GLU quadrics)