Well, as per my previous posts I was having a high fuel consumption issue. Just town driving was giving a return of 19MPG.
These are the things I've done so far which to be honest didn't have any impact...
Exhaust leak test - Visually and aurally by me including a ''marigold'' test. Also for a fiver I got an emissions test inc. them looking for exhaust (specifically manifold area) leaks. All good.
Vacuum leak test - This was a bit hit and miss because you can't really get in to all the places you need to with the carb cleaner. BUT there was no leaks in the places I could get to.
Voltage leak test - Done in the dark to see if there were any sparks or ''arcing'' between the HT leads. Again, I couldn't find anything.
Stuck caliper checked for. Put car in neutral and rolled. No resistance at all.
Cleaned EGR - Performance seemed to increase slightly but nothing really noticeable.
SO.....
I was constantly checking fuel consumption with no improvements at all. THEN....
I decided that as I had a spare MAF sensor (from Ralf) and as my reading from my last TechII was low (9 kg/hr) I took my electric contact cleaner and virtually emptied half a can spraying the sensor and it's connector... left it to dry for about a week in the garage, stuck it in and immediately noticed what I believed to be an increase in power.
Checked consumption today using the brim to first click method and what do you know, with no change in type of driving ...... 25.6MPG

I'm still going to do the other things that have been suggested like swap out the Disspac as I have a spare one.
BUT at least I now have hard evidence of very good improvement. I'll keep checking consumption but I'm going to call this done

Cheers to everyone for ALL your help