Plug certainly didn't feel loose trying to rock it.... hey ho.
Ok to the Drivers side.

Definitely water in the plug well - above the plug 'nut' shape bit that the spanner I don't have would fit onto. Water droplets around the cp for this plug too.
tricky to see here - but other plugs: Middle pretty dry to be honest nothing really to report. Front plug well - the timiest bit of oil round the base of the plug.

Either way looks like this pack is toast too although maybe just hanging in there.
Windscreen scuttle leak:

This was loose all the way along the bottom of the screen. I've cleaned and re-seated it so that it's pretty tight now.

Slightly worried that the drivers side by the wiper spindle is slightly split and won't fit as tight as the rest of it - you can see where the water has run through onto the pipes in this picture

By the way Chris - thanks for the excellent tip for lifting the cp's out using another bolt. It just so happens that these Saab 900 Exhaust manifold bolts happen to be an exact thread match too - what a breeze that was


Finally - all cleaned up and back together while I work out the repair logistics. Started it up. no misfire

Codes are now reading same as before except the misfire reported has moved from #4 to #5 - even though it's not misfiring. I'll assume that it's not happy with the general condition of the cp's and can't now make it's mind up.
Every day a school day - thanks everyone for their help - at least I know exactly what I'm up against.
Cheers
Ian.