Model made in metalness pbr workflow.
Model is subdivide ready, has clear mesh and handmaded UV. No ngons. Tris used only on flat surfaces and have no influence on geometry when subdivided.
Close up render is possible.
I want to draw attention on the fact that the model uses a lot of bolts and this greatly increases the polycount. Also as inside panel.
So if you dont need close up render or opened box you can easily optimize it.
Full model has 65k faces. Closed version without planes is only 29. For easy work blend file has two layers with these two versions of model also as fbx and obj exported separately.
4k textures used: roughness, metallic, base color and height for microdetails on plane.
Model made in Blender 2.79. For render used hdri map and Principled BSDF.