Should be fairly simple... spanner to the advance lever or just a bit of friction to get it off. Block the rewind shaft with a pencil and just keep turning until it's off. There's a screw on the back and one on the left side. After that, it should come right off. If I remember correctly, it's a snug fit, so you'll probably have to wiggle it a bit.
Of course I have a photographic memory: over exposed, under developed, grainy and out of focus
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