Having aligned and taped both rear halves of Victory's mid-deck together I carefully measured out and drew the deck planking & joints as recommended in the magazine. I noted, however, that a coat of varnish was suggest as a way of preserving the lines thereafter.
On the basis that I would be painting this visible part of the decking, however, then any pencil lines would naturally have to be applied post painting and in situ, which didn't appeal at all.
The answer was to scribe over every pencil line with a suitable blade thereby effectively 'tattooing' the lead into the timber itself, as well as leaving clear demarcation lines that would indicate individual planks showing through the painted surface.
I applied a 'mist-coat' of Humbrol mid-stone thereafter to check the overall effect of the scribed planks (and partly to obscure a strong grain pattern on one half of the ply).
Once I've applied the actual finish, it will allow the lead embossed scribe marks to show up just enough to see them through the ports on close inspection.

Rivergypsy