Hi all. Hoping someone maybe able to help with ongoing problems with my Wife's 2.2 SRi Direct Vectra C. This is a long story but I want to pass on as much info as possible in order to get to the bottom of this once and for all - so sorry in advance for going on a bit!

ENGINE (hoping Benny maybe able to help here!)
We have had ongoing issues with the engine. The car initially began to make a light ticking / tapping for 5 - 10 seconds on cold start-up and appeared to be classic signs of Chain / Tensioner failure, and so was replaced by a Vx Technician on the side (car from memory had done about 60k - 65k miles at that time with full Vx History). Turned out the Vx Technician left a nut / bolt that he had replaced somewhere loose in the top of the engine. It ran fine for approx one month, but one evening the nut / bolt must have slid across inside the top of the engine and smashed a rocker & hydraulic tappet - luckily no damage was done to the head itself.

Following head removal (by another mechanic) the top end was rebuilt and ran fine, albeit with the odd stutter on idle. After a week or so, the car suddenly began to tick very louding and sounded like an hydraulic tappet was been starved with oil. The car went back and was back with me in 2 hours. I was told that the high pressure fuel rail was found to be 'loose'. The ticking had gone and never re-appeared. Not sure if this was the problem, but they certainly didn't have enough time to take the head off again. The car ran fine but used a lot of oil, with a large burst of smoke on start-up from time to time. It turned out the Valve Stem Oil Seals were not replaced during the rebuild (bad practice I know).

Later the inlet manifold was replaced due to sticking Swirl Flaps and the EGR Valve was programmed out and blanked off with the latest version of Software updated onto the ECU at the same time. The idle did improve but not fully, athough initially I did think it was fully cured.

Anyway, about 3 weeks ago I bit the bullet and had the head removed to have the Valve Stem Oil Seals replaced and ensured a complete Vauxhall Head-Set was used (don't think there is a non genuine item for the direct anyway) - the RRP for these is £250 alone! This were all duely fitted along with a new Crankshaft Oil Seal (due to a minor leak).

Got the car back and it ran very well. After a week or so, the exact same ticking noise re-appeared that happened approx. 1 week after the last rebuild. I therefore took the car back, but the fuel rail was not 'loose' this time. The ticking has now become variable and only does it occassionally either on cold start up (for 5-10 seconds) or at idle when the engine is fully warm. It hasn't done it however, for the past 2 - 3 days. When the ticking is not there the engine sounds sweet. Any ideas what could be causing this? I've found this clip which sounds very similar to the ticking I have minus the periodic 'cracking noise' - I believe this may have been recorded from someone on here.
https://www.youtube.com/watch?v=KmYaZL0CLIw

However, 90% of the time the car sounds perfect.

GEARBOX
Next issue, the car has now covered 85k miles with no evidence of clutch change (we have owned since approx. 50k miles). The clutch has felt past it's best for a while now but has never slipped. Where we live is very congested so my wife queues to work each day for the best part of an hour -not ideal for the car everyday. Anyway, about a month ago the clutch over heated and 'stunk' exceptionally bad. My wife is used to the journey and this has never happened before in the past 10 years of her doing the journey with this or any other car - so sort of rules out poor driving (maybe?). The clutch cooled and drove fine afterwards, albeit the clutch did feel 'weak' if you know what I mean, it didn't slip, but had a very high biting point.

I then drove the car last week and got stuck in a massive tailback and had to gueue for about 1.5 hrs (serious accident on the motorway). The clutch did not overheat, but after 1 hr every time I enegeaed 1st gear and started to move off there was a massive 'grinding noise'! The car didn't judder, drive engaged fine etc. just the noise was the issue. This was so loud other people alongside could clearly hear it judging from their reactions. Afterwards 10 mins of normal driving after queing removed the noise, it's only when it was queuing for a while that it did it.

I therefore have also taken the expensive plunge and had a new clutch / pressure plate, release bearing and Dual Mass Flywheel fitted. This feels much better and is I believe the contributing factor to curing the tickover 'stutter' we have had for a long while now - so on that front - Result. I was told the Flywheel was completely knackered and covered in a whiteish powder, and that the clutch itself was well worn and beginning to break-up. HOWEVER, yesterday I ended up queing for approx. 15 minutes and low and behold the same grinding noise reared it's head!!!!!!!!!!! Again, the car was pulling away fine, just with this noise. Afterwards 10 mins of normal driving removes the noise, it's only when it's been queing for a while. So, $1m dollar question..... does this sound like the gearbox is on it's way out? What are the options? I don't suppose the engine ticking noise could in fact be related to this and not the engine itself?

Sorry for the long post, but this car is driving me mad, and costing even more money!

Any / All help and advise greatly appreciated!