When you convert an rst over to cossy man do you have two crank sensors?

Ive seen cars with them on the crank and on the cam pulley? The cossy wiring loom only has one crank sensor.

Im a bit confessed any help would be good.

Also where do I get the plate to mount the sensor and pick up plate?

Ive tried jano @ old kids but I cannot get hold of him...

Jim