A direct pitch on top would work great. I've done it twice and one was my RIS (1.105), the other being a big Tripel. I've also done the wash thing for brews below 1.070.
I would try and rack off as much of the Irish red as possible, but I doubt you would get much flavor transfer to a big stout like you're planning.
Primary #1: Umlaut my Kölsch VI #2: Sunrise Wit
Secondary #1: Empty #2: Black Currant Wine #3: Empty
Bottles: Spruced Winter Warmer, Big 50 Barleywine, Framboise Lambic, Russian Imperial Stout, Barolo Wine, Berry Rhubarb Wine
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