It's on the rear glacis plate and has angled edges (part D23 on Tamiya kit) if you're not sure which bit i'm on about.
On my kit the area is simply moulded flat underneath, but I thought it might be a point of interest to model the port open as in the reference pic. However, my references fail to show what the area under the cover looks like (I have a pic of two crew cold starting a Stug Ausf E but ine of them is in the way!) and i'm hoping someone may be able to help me out.
I'd appreciate any info and help you may be able to offer from any of the Stug or Pzkpfw III range.
Many thanks,
James
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