Hi @Anonymous,
I am no longer sure what the question is. Your drawing looks great.
Your titleblock is positioned on a 24x36 page at 1:1. The viewport is scaled at 1/2"1'-0". When I do a Print Preview everything looks as it should. The only extra step I would suggest is to create a named Page Setup that can be applied to your layouts or imported into other drawings.
I made a quick video of this action and also how I like to apply it in a Publish process. Be aware that Publish can use multiple drawings and multiple layouts. I don't ever like to have more than one layout in a drawing in case of any corruption or failure.
So typically, I do all my geometry in a base file(s). Then I create a new drawing for each sheet in the drawing set. I then Xref in a titleblock (in paperspace).
I usually also utilize a Sheetset to help populate titleblock properties and to navigate within my project. I usually start PUBLISH from within the Sheet set and plot all the layouts in all of the drawings.
I have attached my version of your drawing as well as the resulting PDF from my video. If you follow the same process to create your PDF for the print shop they should be able to print it at 1:1 and it should come out accurately.
If you need to stay in modelspace only at this point, then scaling the titleblock accurately will be key. I have attached a scaling chart that I use occasionally to help know how much to scale things up and down.
I did notice that your drawing had two errors when running AUDIT. I purged and also -PURGED>Regapps to remove 28 regapps.
Please select the Accept as Solution button if my post solves your issue or answers your question.
John Vellek
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