You will have to add a light or something if you want to see. There is no external controller, the ECU controls that. A VTEC controller is a separate piece of electronics that overrides the VTEC signal. It's a horrible idea compared to getting an earlier ECU that is actually able to be tuned and modified. You're asking a lot from a single cam VTEC engine I think, the difference in power when VTEC engages is not very big.