Everything is experimental. Each plane/cowl is different. On my Zero, baffle position and opening up the cowl flaps really helped the exiting air. On my X-Cub I played with several cooling ideas before finding one that works. Telemetry really helps figure out whats going on in flight.
Those heat sinks come off. I wonder if you could make two tiny aluminum L-brackets and attach to the side of fins rather than the front.