Modify & Slice Existing STL Model for Large-Scale 3D Printing -- 2

I have an existing STL model that needs to be prepared for large-scale 3D printing and assembly.

my bduget fixed 50AUD if youre not agree dont bid otherise I will report

Requirements:

Analyze the provided STL model.
Split the model into multiple printable parts according to size limitations.
Create strong interlocking joints (lap joints, step joints, or similar).
Add assembly features such as screw holes and alignment mechanisms where needed.
Ensure proper tolerances for easy assembly after printing.
Optimize all parts for successful 3D printing with minimal support requirements.
Deliver organized, print-ready STL files.
Provide an assembled reference file and a simple assembly guide.

I will provide:

Original STL file
Reference images
Client requirements and dimensions

Looking for someone experienced in:

3D Printing
Mechanical/CAD Design
STL Modification
Fusion 360 / SolidWorks / Similar CAD Software

The final result must be production-ready and safe for 3D printing and assembly.