Did you ever read Lord of the Trees by Farmer? It was a companion piece to The Mad Goblin, but the latter featured a version of Doc Savage. The two books told the same story from different points of view; I first found them together as an Ace Double. Fun stuff.
Nope, but I was aware that Farmer did lots of pulp pastiches/expansions. The ace doubles were really cool, I have a handful of ones by the great Jack Vance.
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