docs: minor update to overlays docs

doc/OVERLAYS.org

@@ -64,6 +64,10 @@ Verify the setup:
 
 This basically means that modules will be searched in both paths, with overlay taking precedence.
 
+** Installing with =--use-pep517=
+
+See here for discussion https://github.com/seanbreckenridge/reorder_editable/issues/2, but TLDR it should work similarly.
+
 * Testing runtime behaviour (editable install)
 
 : $ python3 -c 'import my.reddit as R; print(R.upvotes())'

doc/overlays/install_packages.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 set -eux
-pip3 install --user -e overlay/
-pip3 install --user -e main/
+pip3 install --user "$@" -e main/
+pip3 install --user "$@" -e overlay/