22 MB have to get repacked, this means they will be downloaded and re-upload after the repack.
1 MB will be effectively freed by that repack.
44 MB can be deleted without any repack.
45 will be freed by deletion and repack.
6 GB will remain after the prune.
Please be aware that there will be a time when original packs and repacks will live on the server together, and therefore additional space is required for a short time.