Lasgun NPC SWEP

As part of a short machinima I’m currently working on, I require a lasgun NPC SWEP.
To do this, I’d like to use the star wars blaster SWEP script from Dan’s Mega NPC Pack, released by Xystus234, and replace the model with the recently released lasgun from bloocobalt’s Imperial Guard model pack.

I had assumed it would be a simple case of reworking the lua file to point to a different model, and placing the models & materials in the correct folders, but I can’t get it to work.
Could anybody do this, or tell me how to do it properly?

Dan’s mega NPC Pack: http://www.garrysmod.org/downloads/?a=view&id=76197
Imperial Guard: http://www.garrysmod.org/downloads/?a=view&id=97582

Is it doable?