Setting default dxf template

Is there a way to set my default file template as the default for opening .dxf files?

Not that I can think of, no.
When you OPEN a file, Rhino tries to read everything is can from it.
No template is used.
When you create a new file using a template, then IMPORT a DXF file, any layers, block definitions, named annotation styles that were in the Template remain. If the DXF file has any conflicts, (these same named things are in the DXF too), they are resolved in favor of the existing definitions.

What problem are you trying to solve?

Thanks for the response. My workflow involves searching for/downloading and opening .dxf files all the time. My template file has a layout tab with my border plus all my dimensions/Layers/etc. I have to start a new file using my default template and paste the recently opened dxf or iges. I know I can open a new file and then search for the .dxf and import it but it would be better to just have the dxf drop onto my default. Typical process >Customer sends email with .dxf>download>click to open.

While I have you-Here is another:

Is there a way to have Rhino display dimensions in this format: 1-1/2" with the “-” between the inch and the fraction? This is a legacy/convention from the company that goes back 25 years.
Have a great day!

It’s best to post a new question so someone that knows can help.
I do not use Rhino enough to be able to help with that one.
Sorry.