There is no way to uninstall a pack. Instead, to unsubscribe the pack from your account, you only need to remove all users from a pack. In doing so, your Method account will no longer be charged for that pack.
Unsubscribing from a Pack
To open the Manage User Permissions screen:
Click the upper-right profile icon and then click Account Settings.
The next screen shows your installed packs and how many users you have for each. To remove access, select the desired pack in the list.
In this example, we will select the Sales Pipeline pack and remove it from our subscription list.
This opens the Permissions screen for that pack: You will need to expand each app to see the users.
As mentioned before, you need to remove access for all users in every app of the pack to unsubscribe from the app.
In this example, all users have been removed from the Opportunities app and the Web to Lead app. Note the Pack Total is $0/month.
And you're done! Feel free to remove other packs as needed. You cannot, however, remove the Contact Management pack.