finally after more chiseling and persuading with a hammer, the p-bracket has finally been liberated.
its not looking very pretty.
then, i had a go at the engine skin fitting. its been looking dodgy since the last survey so I planned to change all of the skin fittings and ball valves.
As I tried to unscrew the ball valve from the skin fitting, the whole job lot snapped off in my hand. which made me laugh a slightly manic laugh, just the thought of it snapping so easily due to it being completely depleted of zinc, it's the stuff of my nightmares and I've jumped up in the night before now to go and check them for leaks or signs of anything wrong. To have one snap like this, well, I feel fully satisfied now that preventative maintenance is better than any other kind.