I got the inner cup(or flange I think they called it) replaced last Friday and it made absolutely no difference at all. I spent a fair bit of time on Saturday checking over the car and as part of that checked the engine/gearbox mounts. The rear mount(under the bulk head) and the gearbox side mount had lots of play in them, I was able to move the engine a good inch or more in either direction. So I've order those two mounts which should be here today and I'll be fitting tomorrow. I've also got my new wishbones and ARB drop links that I'll be fitting at the same time, so I'll report back what the difference is after fitting.
I've got the car booked in next Friday to have the clutch and flywheel replaced, £330 for labour(exl VAT) and £168 for a re-con dual mass flywheel through Alfa. Anyone needing a dual mass flywheel should consider doing this first as you still get the parts warranty, but it's a re-con and pretty much a third of the standard price of a DMF. I'm supplying a clutch myself, but the garage said they can supply for £150-£200 I think, so next Friday is going to cost me including VAT £585.
It was my choice not to do the drivers side driveshaft as a complete driveshaft and fitting was £420 I think they said and as the other side being replaced has made absolutely no difference at all, I can't warrant spending that sort of money on replacing something that might not be the cause of the problem.
I am hoping that it might be the engine mounts causing the engine to twist, (not rock due to the stabiliser bar at the top) which results in the driveshaft(s) going out of line which causes the vibrating, but I don't know enough about it work out if this is a possibility?! Any thoughts?! I am also quite annoyed that the garage stated they have checked the engine mounts, but they are well and truely gone.
I really don't know where to go after this if replacing the wishbones, engine mounts, clutch, DMF, passenger side driveshaft doesn't resolve the problem. The only things after that I suppose are going to be drivers side driveshaft and then the gearbox!
I did ask the garage to find out about a gearbox overhaul and there is a place called gear link or something that will do it for either £820 or £1420, I can't remember which but knowing my luck, it'll be the most expensive.