cheers Johnny Dog - however none of that actually rings a bell ref the removal/refit of the scuttle panel but it has been a while since i last took that off and i have done other cars that are differently secured since then, hence my confusion now.
Just to be sure we are talking about the same thing, i cannot get the rubber trim at the edge of the plastic scuttle panel to sit tight against the windscreen. I went to see another omega today today and that was even worse. So, are your instructions meant to deal with getting the rubber seal to sit correctly?
Don't forget that over the years if the lower rubber seal has been misaligned, to get it to fit snugly against the bottom of the screen maybe be difficult or possibly impossible to do as rubbers can be awkward to sit or position correctly after years of being out of shape.
I'm not certain whether they are still available from Vauxhall, but for the cost, I may be tempted to replace it with new. Then at least it should sit correctly in the retainer and hopefully 'hug' the lower edge of the screen to reduce any water ingress.
There has been previous discussion on here whether the top edge of the lower rubber should be sealed again the glass with the flexible windscreen sealer - my opinion is that if it doesn't cure it with a new seal, then it shouldn't theoretically do any harm. Not everyone agrees, but not everyone has a leak that is seemingly difficult to cure.
In my 2.6, the scuttle has been off a few times for various reasons but the foam is always dry as a bone, and it has no silicone in the recommended area under the scuttle and it is still on it's original plugs and coil packs with no indication of a misfire through water ingress (67k) yet I have a 3.2 on which the foam is continuously damp (not soaking wet), but on the majority of Omegas I've owned, there is always a degree dampness on the rear passenger side of the engine if not used for a few days, but if used regularly the heat of the engine drys what bit of dampness there is.