Just an update folks, I was able to get temperatures working with OMV5 using the code and guidance provided earlier in this thread by sbocquet. Not as a plugin but by adding a couple of lines here and there, I expect I will have to repeat the process when the next update comes out but the pain in minimal. I needed to keep an eye on the temps on my new OMV5 hardware (BeeLink T4 fanless Atom 8500) that has replaced my trusty Odroid XU4 finally died after 3 yrs of hard service.
If you want to make your updates easy, just save your modified files in a .sav files, than copy them after each OMV update.
There are not much changes even none in those files...