Siegfried, no way of knowing for sure, although, the factory would have done anything for a fee i am sure. The car is so much better with 5 speed. Looks similar to the box in my late 70's Aston V8 Vantage. The throwout bearing is always noisy on these and they are slow shifting. A very heavy and sturdy box. And no, the weight make a difference on these cars which are heavier than a Cobra but still light compared to contemporary super cars. If it needs to be rebuilt don't bother, put it in a box and install a modern Tremec TKO 600. Did you ask the club for any documentation on this particular car?
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