From Salix OS
There are recommended UID/GIDs for use with SLKBUILD scripts: Defaults Slackware UID/GIDs
partimage ======= User: partimag UID: 77 Group: root
Note that recommended UID/GIDs should not be created automatically when the user instal the package.
All informations have to be written in a README.Slackware file which will be in the /usr/doc/$pkgname-$pkgver directory, the user will have to add specific UID/GIDs to his system by hands. A little note in the slack-desc can be usefull.