164 gearbox failure

[jonathan coates <alfa@domain.elided>]

I posted some pictures of the casting of my gearbox which now has a hole
in it. The pics are at www.cdico.demon.co.uk/cars/gearbox.htm if anyone
is interested.
A short while ago I posted the symptoms which were, oil leaking from the
clutch housing and a funny feeling in the clutch pedal. Now that its
obvious what was happening I need to know what caused it. Could the
clutch replaced 300 miles ago be too deep and caught the housing?
Could some debris ( I found none BTW) have got in there and done this?
Anybody have this before?
Can I replace just the smashed casting maybe? If I clean out all the
bits from the gearbox of course.
- -- 
jonathan coates

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