First and foremost update the existing one; if any pending issue are there ,then it will get resolve.
root@Slackware:~# slackpkg update
It will pop up a TUI and ask for package updation,need to select and press ok.Once that operation done.Go to the next step by doing so..
root@Slackware:~# slackpkg upgrade patches
At the end of this operation it will ask you like this :
Searching for NEW configuration files
Some packages had new configuration files installed.
You have four choices:
(K)eep the old files and consider .new files later
(O)verwrite all old files with the new ones. The
old files will be stored with the suffix .orig
(R)emove all .new files
(P)rompt K, O, R selection for every single file
What do you want (K/O/R/P)?
Now it's your call to take,whether you want to do it by hand or the package manager do it for you. I had little to do this specific upgrade so I went for interactive way; like this :
Select what you want file-by-file
/etc/uniconf.conf.new - (K)eep
/etc/httpd/httpd.conf.new - (K)eep
0 -------------------> my selection
/etc/gconf/2/path.new - (K)eep
o -----------------------> my selection
/etc/gconf/2/evoldap.conf.new - (K)eep
o ------------------> my selection
But for huge upgrade, you should fall back to package manager to do the job for you.Or you are curious(you should be!) then do it by hand, and it will take some amount of time.
Hope this will help.