Need Help! Index Capability Encoder work with Viper200?

I'm trying to future proof the system by including as many features now as I can. Would an encoder that has Quadratue and Index work with the viper 200F even though the Index is not required? Or do I have to specify an encoder that is just Quadrature with no Index capability? The way I see it, the Index is just 2 more leads out of the encoder that wouldn't be connected to anything. Is this correct?

thanks
-D