Backing it up a bit, when I saw the above I had another thought. I'd like to see 1) the strake all red: check; 2) the top of the red stripe continue along the same line as the top of the strake: check; but 3) the bottom of the red lift from the fuselage right where the strake ends, going parallel to the top line, leaving a little white below. As if the whole thing were a single constant width stripe, but with part of it, right where the strake is, disappearing into the fuselage.
The blue could then be another constant width stripe, the same width and parallel to the red one, positioned above it so that its top aft corner is on the conder of the fin.
Confession: from the first mention of "Thunderbirds" until post #103, I thought we were talking about the puppet animation TV show.