Asrock C2750d4i (or C2550d4i) CPU Cooler Fan Shroud

DISCLAIMER up front - I am offering the following purely with the view of information sharing and take no responsibility for any harm that may occur to people systems as a result.

The Asrock C2750D4i and C2550D4i motherboards are fairly well documented to have heat issues (which have resulted system failures) - for example see here: https://forums.freenas.org/index.php?threads/asrock-rack-c2750d4i-cpu-temperature-issue.41528/
This situation is certainly not helped by the passive-only cooling