Thanks @Sirtel. Looks like it may just be a drag and drop into SSD\PortableApps\calibrePortable using your link.
Interesting that the portable version is available on calibre-ebook.com but not portableapps.com. I couldn't find any information about who is maintaining the portableapps.com package. ¯\_(ツ)_/¯
Thanks! I will tinker with this
Found this too.
https://www.mobileread.com/forums/sh...d.php?t=300305