Dave K0MBT has been working to keep his power transistors cooler. Initally he added a 80mm fan to blow across the transistors and board.
When doing ft8 he would get significant heating of the power transistors running on a 13.8v linear power supply. The transistors would heat up enough to make them too hot to keep his fingers against the surface.
He has, therefore, added a shroud similar to the one shown covering the stock heatsinks. It did not help that much. He had a fairly small but 1″ tall computer heat sink, cut it in half and tapped in mounting holes. The shroud had to be redesigned to fit them but now he can only feel a very slight degree of heating wile running the FT8 tuning feature.
This worked so well, he has added a similar heatsink to his BITx40.