I've welded on my blaster frame without disconnecting anything without any damage. The trick is to make sure you have a good strong ground (with the ground clamp from the welder) near the weld point.
As long as you make sure you're going to make a good connection, you should be good to go.
If you're concerned about it, the only thing I can recommend is to disconnect the CDI box.
As long as you make sure you're going to make a good connection, you should be good to go.
If you're concerned about it, the only thing I can recommend is to disconnect the CDI box.