G'day Louis (@lgardner),
Thanks for the compliment.
I did trial your method more or less (using acrylics and without the clear barrier) on the spare tailplane, but decided that the contours and rivets, etc on the wing would make it a little difficult to keep the lines straight.
If I had a bit more time up my sleave I might have tried to find a suitable non acrylic barrier layer (covid lockdowns have not helped).
Thanks again for your interest and advice..