The "standard" is just what they call the first year incarnation of the CX. It's a model onto itself.
some quick tells are:
The forks are smaller (33mm) than the other CX's.
The deluxe has the king/queen seat while the standard has the flat seat.
plastic nacelle, only on the standards
the standards have big wide stripes on the gas tank,and they came only in candy apple red and black (in North America)
The round brake reservoir is also another tell for a standard model vs the rest.
The standard's all have silver comstar wheels, the other's black reverse comstars.
Standard has 18 inch rear wheel while the deluxe a 16 inch.
Standards have black plastic radiator shrouds.
120 MPH speedos on the standards and unique idiot light setup
30+ years out, no matter how may parts have been swapped and frankenbiked, there's always something left that hints at the original.