Re: press plate and throwout
Remember - the TO bearing for a Borg and Beck - fingered type - and a diaphram type are different.
The B&B has a flat face on the TO brg (finger ends are rounded,) where the diaphram type has a rounded TO face (the diaphram fingers are flat.)
You can't mix them up successfully.
The angle of the fork - as it passes through the entire movement should start just shy of 90 degrees, pass through 90 midway, then end up about the same angle past as it started. That gives maximum leverage.
Sometimes you have to use a longer - or shorter fork pivot ball to achieve that. Or a longer or shorter TO bearing.
If the assembled height of the fingers (measured from the flywheel to the finger ends when torqued down) has changed from type to type, you have to compensate for the difference.