Deeper guides for Scalextric

Quickest, easiest, cheepest solution I've found is to put the back half of the blade in a vice and tighten. Retains the thickness at the front of the blade, but gives extra depth at the back with a smooth transition between the two. My initial experiments were to get extra depth for the old C7030 PB sensors. This approach enabled me to control the amount I increased the depth by the tightness created in the vice.