Quake 2 Lost Marine shotgun/chaingun

Hey guys, I was wondering if anybody could help me out with this. I'd like to replace the Doom 3 chaingun and shotty with the models from Quake 2 Lost Marine for each, but I have no idea how to do so.

I can't even load the mod up properly with the latest doom 3 patch, and if i replace the .dlls the weapons don't show up in that mod.

Does anybody know how to do this? I'd really like to use those in regular Doom 3. Actually I'd probably prefer the super shotgun as a model replacement for the doom 3 shotty because it looks so cool

Here is a mod that enables running the Lost Marine mod with the latest Doom3 patch:

http://www.the-emz.com/run13on131/

As for converting the weapon models, do you have some basic modding experience with Doom3? How to create a mod pk4 file?

None really at all unfortunately.