Hi Trevor,
The putty knife trick only works if one side of the clutch had separated from ether the pressure plate or the flywheel with about a 1/8" gap. If you have pressed the clutch petal in, but nether side of the disk has released, then you have another issue.
If you Successfully ran the putty knife all the way around both sides of the disk, then the clutch system isn't working correctly, or the wrong components were used.
When you press the clutch petal down, does the slave cylinder push the release rod out the full stroke? If so, then there is an issue with the clutch assy.
The person that you bought it from may have used the wrong pressure plate for the series V. There are 2 different types of pressure plates. The early cars had a spring type of pressure plate, and the series V has the diaphragm type of pressure plate. The pedestal that holds the throw out bearing arm are different heights depending on the pressure plate type. The throw out bearing is different between the 2 types also.
There is also a MG pressure plate that is supposed to work with the Alpine, but I don't know anything about that setup.
Guess you are down to the last resort now, pulling the transmission.
It can be done without pulling the engine.
The procedure has been discussed on a different thread here.
First thing to do is pull 1 bolt out of the bell housing, and go to your parts store and get 2 bolts of that size about 6 or 8" long and install them on opposite sides of the bell housing before you remove the other bolts. This will prevent the transmission from unexpectedly sliding out and hitting the deck when the last bolt is removed. Also, when installing the transmission, they will act as guides in aligning everything up when you install it.
Be sure to remove the speedo cable, as sometimes that gets overlooked.
I don't recall having to remove the radiator due to fan to radiator clearance, but check that. Its been a lot of years sense I pulled the transmission with this procedure.
Do all of the regular things, Drain the oil, pull the drive shaft disconnect the clutch slave cylinder, starter and disconnect the battery etc.
Check the fuel line at the pump from the tank and make sure it won't bind when the engine tilts back, otherwise remove it and seal off the end to keep the gas from running out.
You will have to pull the intake and exhaust manifold from the head and perhaps the upper radiator hose. Check for anything else that might bind under the hood. Put the car up on jack stands as high as they go and put some sort of safety blocks under the front and rear of the car in case one of the jack stands slips. Support the bottom of the transmission with a floor jack, remove the transmission cross member bolts and remove the bracket, Then start lowering the transmission. Have a helper hold a small block of 3/8" plywood between the valve cover and the firewall then let the transmission down until the valve cover rests on the wood. The transmission should be tilted down low enough to slide back and come out after you remove the guide bolts. Lower the floor jack and move the transmission out of the way.
If you see any seepage from the input shaft or the drive shaft seals on the transmission, now would be a good time to replace them.
I know you have gone through a lot with this problem. Even asking questions here on the board doesn't give you all of the answers. It is hard to give advice, when we are not standing there looking at your problem in person. If you were close to me, would have come over and given you a hand.
I can only relate my experience with the same type of problem that I had. Didn't account for perhaps the wrong parts used, broken clutch plate, although I never have heard of one that came apart to the point that it wouldn't move.
I guess I assumed that the clutch system was working and pressure plate was releasing one side of the disk.
Will be checking this thread often sunday, so let us know what you find, and I or others here will try to answer any other questions you might have.
Good luck.
Al
