Vapor lock issue?

Just wanted to see if anyone has had issue with vaporlock out there. I have a 1970 Dart Swinger with a 318 and a 4 barrel swapped on. Lateley I've had issues with fuel at idle after running on the highway. I can watch the fuel filter dry up at idle, then it really starts to sputter. Give it some gas and enough fuel gets pumped to fill up the filter eventually. Lines in the engine bay are well clear of heat sources. Only other thing I can think of even possibly causing a problem is the fuel line back by one of the tailpipes, but even that is at least an inch away. Any input greatly appreciated!