One of the perils of adding cosmetic fishplates is that if you are using the rather nice P4 Track Co plastic ones, you need to cut them in half (unless you are putting them on an actual rail joint).
When laying the track on Callow Lane, I prefered to lay the track more as lengths of (made-up) flexi track, using their components, rather than actually try to lay individual 45' or 60' panels.
This means that I now have to cut small grooves in the tops of the rail heads at the appropriate intervals and glue fishplate halves on each side of an otherwise solid rail.
Apart from the extreme fiddliness of cutting the plastic items in two, you then need to square up the ends where they have come off the sprue, and cut off the remains of the tiny plastic joining piece on the back of each fishplate half, so that it will glue nice and flat against the side of the rail.
Of course, once it's all painted and weathered in, there could be a risk of it all disappearing into the overall scene of the layout, but I'm hoping that those on the main running lines at least will stand out a bit, as the rust colour will be fairly light (based on Humbrol No.62 Matt Leather), with the fishplates freshly oiled by the PW, and thus a darker colour.
That is, unless the men in the white coats don't cart me off first....