Upgrading from 7.1.0.4 to 7.5

Hi I have been searching for a simple way to upgrade from 7.1.0.4 to at minimum the latest patch of 7.5

First, Is there a simple easy to read guide on doing this? Most I have seen have been a bit complex and I am by no means a backup admin.

Second, Are there any known bugs still in 7.5 that may not be in 7.6?

Third, is the upgrade a long process? We have a short maintenance window on Thursdays (AM) we would like to do this in that window.

Thanks,

CM