The shop that just built me my Q-Jet told me I should do a fuel line purge before installation. I haven't heard of this before. Anyone have any thoughts?

 

I've never heard of that. You could remove you fuel pump to carb hard line, and blow compressed air through it if you wanted to. From tank to pump would be kinda hard though. Maybe disconnect the tank to pump lines, and blow compressed air from the engine bay back. It'd basically blow bubbles in the tank.
I think it's a waste of time. I'd just put in a new fuel filter, then change it a week later. Then be done.