Design scribblings

Here is my first rough scribblings. If you cannot read my writing (and sometimes I can't read my writing!), here is a summary of the drawing.

HO scaling = 1:87.1

Trailer specs:

• Length: 40' or approx 140 scale mm
• Width: 2900mm or approx 33 scale mm
• Height from rail to deck top: ~ 1000mm or 11.5 scale mm
• you could use a flat deck with a underneath spine. I am thinking of something similar to the NSW NOCY wagons that my frienf Craig models but without the sides.
• Using a flat deck would be fairly easy if the containers were permanently fixed to the trailers, thus no deck detail required

Power unit specs:

• Length: ~ 60' or approx 210 scale mm
• Width: same as above
• Height: from rail to cabin roof 3010mm (1000 + 2010mm) or 34.5 scale mm
• same basic idea with the deck. However I am thinking the cabin should be removable for ease of access to the motor &/or decoder &/or LEDs. Either a couple of bolts for locked fit or some angle inside for a push loose fit
• referring to photos, I think the windscreen panel might be at approx 60 degrees
• a guestimate of height from deck to bottom edge of windscreen angle panel of 1000mm or 11.5 scale mm
• photos of the cabin would indicate a edge chamfer of maybe 400mm or 4.5 scale mm. Would this be too fiddly or could I use modeller's licence just to keep a basic box shape?
• As for the LEDs, I am thinking Headlights ( white x 2), Marker lights (white/red 2 x 2) directional, Ditch lights (white x 2), Number boards (white x 2). The number boards and headlights could potentially be lit via fibre optic from a common source LED. Something to discuss further.

As for styrene thickness, base maybe 2mm and cabin 1mm.

So if anyone is following this blog and is prepared to go over my logic, assumptions and maths, I would be grateful for any feedback.