Where did my original .bash_profile go?

It's nice that we make a backup but…
 * what if a back-up already exists?
 * what if this is the 2nd, 3rd or 4th time I'm executing the script?

We backup to .bash_profile.bak or .bash_plofile.bak.{count} if .bash_plofile.bak already exists.
iow
.bash_plofile.bak if not exist
.bash_plofile.bak.1 if exists
.bash_plofile.bak.2 if 2 exists
.bash_plofile.bak.3 if 3 exists etc…

Newest backup with the highest number.

install.sh

@@ -3,6 +3,12 @@
 BASH_IT=$(cd ${0%/*} && echo ${PWD})
 cd "${OLDPWD}"
 cp "${HOME}/.bash_profile" "${HOME}/.bash_profile.bak"
+BASH_PROFILE_BAK="${HOME}/.bash_profile.bak"
+if [ -f "${BASH_PROFILE_BAK}" ]; then
+  list=($(ls "${BASH_PROFILE_BAK}"*))
+  BASH_PROFILE_BAK="${BASH_PROFILE_BAK}.${#list[@]}"
+fi
+
 echo "Your original .bash_profile has been backed up to .bash_profile.bak"
 
 cp "${BASH_IT}/template/bash_profile.template.bash" "${HOME}/.bash_profile"