diff --git a/cc1541.spec b/cc1541.spec
index 9c7c399..6e5d2b0 100644
--- a/cc1541.spec
+++ b/cc1541.spec
@@ -29,7 +29,7 @@ using either SPEED DOS or DOLPHIN DOS BAM-formatting.
 
 %prep
 %autosetup -p 1
-sed -i -e '/.NOTPARALLEL:/d' Makefile
+sed -i -e 's![ \t]*$!!g' *.c %{name}.1* LICENSE.txt README.md
 
 
 %build
@@ -54,6 +54,7 @@ sed -i -e '/.NOTPARALLEL:/d' Makefile
 %changelog
 * Sun Jan 29 2023 Björn Esser <besser82@fedoraproject.org> - 4.0-4
 - Patch Makefile to be thread-safe on all targets
+- Clean trailing white-space in some files during %%prep
 
 * Sat Jan 28 2023 Björn Esser <besser82@fedoraproject.org> - 4.0-3
 - Apply two upstream patches fixing verbose file allocation table printout