I have a 65 GTO, 389 Tri Power, 4 speed completely stock except bored out 30 over no A/C. After rebuilding carbs, replacing vacuum hoses, replacing distributor she is running very good however since its getting warmer out here in the southwest it has vapor locked a couple times after shutting off and heat soak, does not want to start until about 30 min of cool down. I have read that I should install a vapor return line back to the full tank to remedy this problem. Can someone one here tell me the proper way. Should I purchase a fuel tank sending unit with the return line or just run a return line to the nipple located on the fill neck behind the license plate?