This is how I've attached the brake switch on my '55 Plunger. I made a stainless steel 'P' clip for the switch. I chose not to use the normal spring as the operating connection as I couldn't see any point and it looks ugly. I've used a piece of thin brazing rod which is held on the brake rod with a small aluminium 'P' clip, (designed for clipping cables to walls but bent to a P). I hope this helps.