[Q] Remove old CynogenMod files Okay?

HTC One X
OS: CyanogenMod 10 ver. 10-20121214-Nightly-endeavoru

Two questions.

1. In the folder /sdcard/clockworkmod/download/
a lot of files (like 2047741211) that appear to be from previous downloads of CyanogenMod Nightlies downloads.
Can I delete all but the most recent ones?

2. In the folder /sdcard/clockworkmod/download/get.cm/get/jenkins/
There are a lot of folders with the nightly download files. Example: cm-10-20121009-NIGHTLY-endeavoru.zip
Can I erase the zip files?

Is there a way to do this when I download the new nightlies? That would make life easier.

I want to do this to free up space in the sdcard memory.