Modify AutoCAD File & Insert Round Gutters

I need an experienced CAD professional to modify an AutoCAD (.dwg) file. The task involves altering existing structures, adding new components, and adjusting dimensions. Additionally, I require round gutters to be inserted into the design.

Ideal skills and experience:
- Proficiency in AutoCAD
- Previous experience modifying CAD files
- Capable of adding new components and adjusting dimensions
- Familiarity with incorporating gutter designs into CAD projects