CAD and manufacturing design of rat barrier cleaning box

Design a Stainless Steel Cleaning Box for a Sewer Backwater Valve (Rat Barrier) Project Description I am looking for an experienced mechanical design engineer / CAD designer to design a stainless steel cleaning box for a sewer rat barrier (backwater valve). The project should result in a fully manufacturable design, including production drawings and 3D CAD files. I already have: Photos and dimensions of the rat barrier A rough concept of the cleaning box A clear idea of the functionality I need someone to convert this concept into a professional engineering design. Purpose The cleaning box will be used to safely clean a sewer rat barrier using a pressure washer. The operator should simply: Insert the rat barrier from the top. Let it rest on a support washer (so it hangs by itself). Close/connect the pressure washer. Activate the water. All dirt and wastewater remain inside the box and drain through the bottom. The goal is to avoid dirty splash water while making cleaning fast and easy. Box Requirements Approximate dimensions: Width: 500 mm Depth: 400 mm Height: 500 mm Material: Stainless Steel AISI 304 or preferably AISI 316 Construction: Open front Top plate with center hole where the rat barrier is inserted Rat barrier hangs on a stainless support washer around its shaft Bottom plate with drainage holes (or perforated plate) Fully welded construction suitable for fabrication by a local metal workshop Internal High Pressure Cleaning System The box should include an internal pipe manifold with approximately 4 high-pressure spray nozzles. The nozzles should be positioned so they clean: Front, Back, Both sides and Bottom of the rat barrier I prefer using standard off-the-shelf stainless steel pressure washer nozzles, fittings and pipe components available in Europe. The design should use commercially available parts wherever possible. Water inlet: Standard pressure washer hose connection Please recommend a suitable connection type (BSP/NPT/Quick Connect). Deliverables I need: 1. 3D CAD Model Including complete assembly. Preferred formats: STEP (.step / .stp) Native CAD files (Fusion 360 or inventor) 2. Manufacturing Drawings Complete fabrication drawings including: Overall dimensions Material thickness Welding indications Hole dimensions Pipe routing (very important and thinking it's easiest to do on the outside. Nozzle locations Support washer dimensions Drain plate dimensions 3. Bill of Materials (BOM) Including: Stainless fittings Pipe dimensions Spray nozzles Couplings Connectors Fasteners (if needed) Please specify standard parts that can be purchased from industrial suppliers. 4. Renderings A few realistic renderings showing: Outside view Cutaway view Internal pipe system Nozzle positions Rat barrier installed Design Goals The design should be: Simple to manufacture Easy to clean Robust Made from standard stainless steel materials Easy to maintain Minimize splash outside the box Provide effective 360° cleaning coverage Use as few custom-made parts as possible Files I Will Provide I will provide: Photos of the rat barrier Approximate dimensions Sketches of the cleaning box concept Reference images showing my idea The Ideal Freelancer: I'm Looking for someone with experience in: Mechanical engineering Sheet metal design Stainless steel fabrication Pressure washer systems Industrial cleaning equipment CAD design for manufacturing Please include examples of similar mechanical or industrial equipment you have designed. Bonus If you can also suggest improvements to the concept (better nozzle placement, easier manufacturing, improved drainage, lower cost, etc.), that is highly appreciated. I am open to design optimizations as long as the final product remains practical and economical to manufacture.