FireArms - Quick Gun Assemble

Hi, I am quite the noob with scripting and have a hard time getting some parts in my script.

I am working on a script that allows you to pick a gun frame, segments that you wanna add (Barrel, Magazine,...) and quickly make some iterations with different scopes.

What I have working:
* Selecting parts (Also multiple parts in one list)
* pick helpers
* assemble gun

What I still need to do but cant get to work:
* if I select multiple object it shows up in the list but I want to assemble with random object from that list.
* Unwrap function will change to a render option with time stamps and extra info

I would be a real help if someone can point me in the right direction with some things.

If you also think I should add something to it, pleas tell me so I can get the max out of this script.