For anyone else looking to remove cranks that aren't good for anything else, I can thoroughly recommend boiling the kettle, pouring hot water over one of the arms and whacking it hard with a mallet. I used the back side of a hatchet - came off after three blows no probs. Repeat for other side. I'd hold the frame with one hand while doing this, you probably don't want to be resting the frame on something whilst battering the shit out of it.
Also, I'm replacing the BB - if you're not doing this I'd be wary of fucking the axle.
Just for the record:
For anyone else looking to remove cranks that aren't good for anything else, I can thoroughly recommend boiling the kettle, pouring hot water over one of the arms and whacking it hard with a mallet. I used the back side of a hatchet - came off after three blows no probs. Repeat for other side. I'd hold the frame with one hand while doing this, you probably don't want to be resting the frame on something whilst battering the shit out of it.
Also, I'm replacing the BB - if you're not doing this I'd be wary of fucking the axle.