A second start for my "White Swan" reefers

[modelsof1900]

The roofwalks are glued on roof supports and what I would like to have - the free view under the planks.


Drilling holes for the supports of roofwalk ends using a drill jig.


Inserting four bolts with square heads ...


... and adding the supports - and ready are the supported roofwalk ends.


Ok, it was a bit more work than I have written here in two phrases. All bolts are inserted in pre-drilled holes and fixed by a drop of AC and it is fixed until end of car's life, I hope.

Fixing of planks has started.
Thin, very thin wire pieces are placed in pre-drilled holes, nailed with a very small hammer like real nails and grinded down on the ground. All.


The small problem - there are 110 "nails" per car and that five times. I think that the next post will follow in a month or so?

But first comes my question - again one. Or more.
In next picture I have sketched a few alternatives for plank laying of a roofwalk.


I nowhere did found pictures or drawings of divided planks of wooden roofwalks. I'm sure that never planks were laid in full car length. But how they were divided and were laid on the roof?
All cuts at one position how I have sketched in sample 1?
Or mixed with planks of varying lengths - Sketches 2 to 4?
What is your opinion? Do you know pictures of such samples or do you know other sources where I can get a few more info?
I would be lucky about your answers and ideas. Thank for your help!