Using a function to remove undesired text from sys_model to improve code readability

[rdwebdesign]

What does this PR aim to accomplish?:

Simplify the code and improve maintenance and readability.

How does this PR accomplish the above?:

Replacing many lines using shell parameter substitutions with a function (using awk) to clean up the string.

Link documentation PRs if any are needed to support this PR:

none

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