I am installing a suspended ceiling in the basement and I do not want to use
Drywall to conceal the HAVC. The new suspended ceiling would be about
10" above the bottom of the HAVC. I was thinking of using the suspended
Ceiling wall angles, main beams, tees, etc. to wrap the HAVC (3 sides).
Is this a good way to accomplish this. If not, any other ideas?

That's what we do in the commercial world and the res basements. The only code problem could be your fire rating for the tile you are using as to how close it should be and not in direct contact with duct and have the necessary air gaps.
Many time you will see a commercial drop ceiling go vertical one to hide mechanicals so it can be pulled out later for access to that mechanical

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Thank you for your answer. This leads to another question.
Where can I find information on how to install this type of soffit? I looked at the library
For some books/videos and also checked the internet with no luck.
Thank you again in advance of your answer.