As well as the dozen or so small bolts holding the box onto the block, there are a couple of dowells as well that may be tight and stopping the box from coming off. DO NOT try to lever it off with a screw driver or similar item - you will damage the alloy mounting face of the gearbox. Get a soft hammer or a block of wood and tap the gearbox away from the engine block. Make doubly sure you have undone all the bolts first, there are a couple right up near the crank pulley that are easily missed.
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Curly
'64 Cooper 'S' (Group Nb spec)
'67 Mini Marcos GT
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