Were there any Goldwater-Humphrey voters?
It looks like there were many in the deep south.
-Goldwater-Wallace voters were not in any sense Goldwater-Humphrey voters.
I've yet to see any compelling evidence that Wallace voters favored Nixon by any significant margin over Humphrey as their second choice, honestly. I'd be willing to believe a well-researched case for such, but all I ever hear now is, well, people's opinions.
-1972 was not enough for you? Compare the vote in various MI counties, 1960 and 1968. Macomb Wallace voters broke for Kennedy in 1960; Livingston and Oakland Wallace voters broke for Nixon in 1960. There were many more of the latter type than the former. Both the Wallace counties in Oklahoma went for Nixon in 1960. And Humphrey was tarnished in the South by Johnson's civil rights record; not so for JFK.
Have you seriously not read
The Emerging Republican Majority?