Wow that's a big salmon! I've never seen one that big dead or alive. Do ye have any local grayling info? Baz maybe?
I've actually got 2 boxes of "grayling flies" one tied by a well known uk guy and I've never even tied one on!
I have fished the Isla maybe 5 times and only had some small brownies, have only had grayling off of the Dean which runs into the Isla and can be fished off the same permit. Nothing prolific tho
Seen Plenty of grayling on the Earn on the other hand! Note i said seen, have caught a few but have seen alot being caught also!