PhpStorm 7.1.3 not showing 8 when I check for updates

You must have chosen to ignore updates once, or something else had  happened. Please try removing options/other.xml  from WebIde70 configuration directory, start PHPStorm, make sure that the update channel is set to "New Major Version Releases and check for  updates.
But note that there is no automatic (patch) update between major  versions, updates are supported for minor subsequent releases (like  5.0.1->5.0.2) only. You need to download a full installation package  from https://www.jetbrains.com/phpstorm/download/http://www.jetbrains.com/webstorm/download/, install it to the empty directory and use your key to register it.

Thanks Elena.

If I use the installer for 8 and choose to uninstall 7.1.3 during the install will it carry over all settings and external scripts, etc?

If you choose to uninstall 7.1.3, you will be asked to confirm if you like to delete caches and settings (both options off by default). Leave them as is (off)  to avoid deleting settings. Then on first PHPStorm 8 start you will be prompted to import settings from previous version

Thanks, that worked.