Roland, thanks a lot for your reasearch and for the pointer of the Bf109K-4 found in München-Riem. I didn't think of that one, but you are very right, it seems to be out of the same batch. The brighter colour bordering the Cockpit section points to a RLM81/82 painting, on the contrary the colours on 33 6/5 141 may be darker,like 81/83 ???. The rest of the pattern is almost identical.
It's a nice theory to use the position of the WNr. to differentiate between the K-4 production lines. I think we can already see a clear trend in this direction and maybe we'll find some more effidence for that. A really great perception!
For the WNr question, I'm already trying to get a better scan by the author, but I haven't got an answer so far. But I'll keep you all up to date.
Until I'm holding on a 5 rather then a 6
The gap breaking the rounding is way to big to be a fillet of the stencil and also the upper bar is way more horizontal than it would be with a 6. But the opinions differ on that case.
You are right 336141 would be a sensation.