Just spent an hour doing my rev counter conversion from RVI type to RVC. It was easy peasy, and I now have a rock steady revcounter. All you need to do is connect the 2 bullet connectors together on the original RVI wiring, put the spade connector on thespade of the RVC tacho, and run a wire from the male bullet connector on the RVC tacho to the -ve terminal of your coil. That's it! The hardest part was routing the new wire through.