I did some experiments with a 12V fan and will post the results.
in normal operational conditions, monitoring for about an hour
Adding this fan on top of the radio
this is results after about 30 minutes.
Conclusion
By adding a 120MM fan on top of the radio, the temp is kept low and stays low, of course some mods can help and reduce noise.
I will be doing more work on cooling for this radio and maybe modifying the top cover to add a fan that is low noise and high cooling.
73's