Editing a 3d object

I am looking for a skilled freelancer who can edit a 3D object in .stl format for a 3D printing project.

Ideal Skills and Experience:
- Proficiency in 3D modeling and editing software
- Experience in editing .stl files

So I found this project:
https://www.printables.com/model/612585-starlink-rectangular-dishy-flat-mount which is a remix of this project: https://www.printables.com/model/429365-starlink-rectangular-dishy-flat-mount-bezel

My problem is, that after fitting the bottom (3mm acrylic sheet) to the print and screwing it on, the mounts on the side would be in the air, as the acryl adds 3mm and the head of the screws another 1-2mm.

So I am looking for someone who could raise the bottom of the 3 mounts 5mm.
Keep in mind though that only half of the mount has to be raised, as the other half is covered by the acrylic sheet. Have a look at the attached picture for reference. Blue has to stay at the same level, as this is where the acrylic sheet is attached and red needs to be raised 5mm to make contact with the ground.

Please send me offers.