If you use a jack, or the studding, washers and nuts method, you have no way of making sure each stay is moving equally, and won't know until you put your wheel back into the frame if you have cocked it. A 5 foot piece of 2x4 is your friend. I've only done it with 531 frames, but much less force is required than I envisaged at first. The only shag factor in doing it is removing the front mudguard if you have one.
If you use a jack, or the studding, washers and nuts method, you have no way of making sure each stay is moving equally, and won't know until you put your wheel back into the frame if you have cocked it. A 5 foot piece of 2x4 is your friend. I've only done it with 531 frames, but much less force is required than I envisaged at first. The only shag factor in doing it is removing the front mudguard if you have one.