The difference is in the ECU. The older style ECU had 5 pins. The new style has 4 pins and does not have to use the dual ballast resistor.
Basically, it works like this... With the old ECU, you turned the ignition key to "start" and the current ran through one side (.5 ohm) of the ballast. This limited the current slightly but still more current passed than when in "run". The car starts, you release the key into "run" position and the current runs through the the other side (5 ohms) of the resistor. This limits the current even more.
With the new ECU, with the key in "start" there is no current passing through the ballast resistor. Key in "run" and the current passes through the (1.2 ohms) resistor.
So.... You need to wire your car correctly for the new system. It will run the way it is, but it's not optimal. You also need to get rid of the POS scotch-lok garbage that is splicing the wire.
Regarding the condenser, yes, keep it. It will help prevent radio static, especially on the AM band.