Just extract/unzip the pak9 file to your Kingpin folder. This will place the pak9 file in your kingpin/main folder.
If you already have a pak9 file in your main folder then extract the new pak9 to a temporary folder somewhere and rename it to another number such as pak3, pak4 etc which you don't already have. Then copy it to your kingpin/main folder.
We have several replacement sound packs such as Serious Sam, South Park etc which you can check out here.
I recently checked the homer model zip file and found that the skin for the baseball bat that Homer holds instead of the pipe was not included. I also realised we had several different skin packs for the Homer model and two zipfiles of Homer's extras.
So what I have done is put all these files together in one homer model zip file and called it male_homer_complete.zip.
It includes all the Homer model files, all the skins for the model and all the extras (nacho hat, glass, cigar, beer hat and dummy [pacifier]).
You can download the complete Homer player model from here.
The hooks are in pak3 files. Just extract/unzip the pak3 file to your Kingpin folder. This will place the pak3 file in your kingpin/hitmen folder.
The zipfiles include an autoexec.cfg and a binds.cfg for hitmen. You only need these if you don't already have these files in your hitmen folder. If you do need them just extract/unzip them to your kingpin folder and they will be placed in your kingpin/hitmen folder.
There is also a readme included in the zipfiles with more information on how to use the hook in game.
If you install one of these custom hooks and want to try it out then go to the Luschen Hookmatch Hitmen server (22.214.171.124:31511).