Figuring Out Custom L4D2 Survivor Viewmodels

I just recently tried replacing the viewmodel (i.e. the arms of your own character in-game) of Rochelle to the one that the Jill Valentine model should use. I got the viewmodel working in the game, but I need to re-rig it. My usual "copy-paste weightmap" technique for rigging didn't quite work on that model. I'll have to rig manually, but that shouldn't be too difficult.