Whats the best way to delete old package?

We are on 7.5 SP1 

We now have some older packages that have been updated with newer versions a few times etc, and we are wanting to make sure we can clean out some of our legacy packages and policies.  We have disabled the policies but eventually things may get cluttered and confusing with just a version number difference.

If I go and delete the packages, policies, and software releases etc will they clean up off the package servers as well?

Just wanting to make sure I do this the most efficient way so that all the references are gone and don't start causing errors in my logs.