Get a specific content from xml and compare - powershell

Question

I have many compressed files that has inside an xml file with Package ID = Guid.
In any file the Package ID should show more then one. some of them will be 000000000 so I should ignore them. The goal is to collect all the package IDs in the file from all the compressed files and compare between them. If 2 files has the same package ID I want to know who has them.
So far I have a script that open all the compressed files and read the text file inside and replace a string (Not as xml)
$fileToEdit = "vip.manifest"
$toReplace = '<Prop Name="WarningDuringUpgrade" Value="True"'
$replaceWith = '<Prop Name="WarningDuringUpgrade" Value="False"'
function ModifyFiles($Manifests)
{
foreach ($file in $Manifests) {
try {
$zip = [System.IO.Compression.ZipFile]::Open($file, "Update")
}
catch {
Write-Warning $_.Exception.Message
continue
}
$entries = $zip.Entries.Where({ $_.Name -like $fileToEdit })
foreach($entry in $entries) {
$reader = [System.IO.StreamReader]::new($entry.Open())
$content = $reader.ReadToEnd().Replace($toReplace, $replaceWith)
$reader.Close()
$reader.Dispose()
$writer = [System.IO.StreamWriter]::new($entry.Open())
$writer.BaseStream.SetLength(0)
$writer.Write($content)
$writer.Flush()
$writer.Close()
$writer.Dispose()
}
$zip.Dispose()
Write-Host "$entry for $file was updated"
}
}
The tag called Package + ID=Guid