Most artists are so used to doing everything themselves that delegating a task never occurs to them.
Well, it finally occurred to me, and I am glad it did!
Here's my CAD engineering drawing, showing the metal structure that houses the wood carving.
I explained what information was needed and showed Tom Houha the full scale cardboard model.
He listened to me, took measurements and photos, and sent me the PDF a few days later.
What a relief!
It's my idea, my art, my model. I made them all, BUT doing this kind of technical illustration would have taken me forever and not looked as good. It's a big relief to have a professional drawing with all the correct information to present to TriMet and my metal fabricator.