A simple vapor return line like what you want to do works great at eliminating vapor lock. The line must be restricted as mentioned. How you plumb it is your business but it works great. I did the same system on a 65 Satellite 413 with dual quads and the throttle response was crisp like fuel injection with my vapor lock issues a thing of the past. That was in the 1990's and the same system is still working great today on the same car. This is basically the same thing the factory did in the 80's to combat vapor lock with the fuel filters with the 3 nipples. R. Eherenberg did an article many years ago in Mopar Action describing this same cure for vapor lock. Good luck.